Vulvodynia:

Toward Understanding a Pain Syndrome

Proceedings from the Workshop

April 14-15, 2003

U.S. Department of Health and Human Services

National Institutes of Health
Vulvodynia: Toward Understanding a Pain Syndrome

Proceedings from the Workshop

April 14-15, 2003

Sponsored by these components of the

U.S. Department of Health and Human Services (DHHS), 

National Institutes of Health (NIH):

National Institute of Child Health and Human Development (NICHD),

Office of Research on Women’s Health (ORWH), and

NIH Office of Rare Diseases (ORD)

Edited by:

Phyllis Leppert, M.D., Ph.D.

Reproductive Sciences Branch, NICHD, NIH, DHHS

Maria Turner, M.D.

National Cancer Institute, NIH, DHHS

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Table of Contents

Introduction.................................................................................................................................... 1

Session I: Overview and Epidemiology........................................................................................ 1

Dr. Maria Turner, National Cancer Institute (NCI) .................................................................... 1

Dr. Barbara Reed, University of Michigan................................................................................. 2

Dr. Bernard Harlow, Harvard University.................................................................................... 3

Dr. Mary Margaret Chren, University of California, San Francisco .......................................... 4

Dr. Elizabeth G. Stewart, Harvard University............................................................................ 6

Dr. Daniel Handel, NIH Clinical Center..................................................................................... 8

Dr. Hope Haefner, University of Michigan................................................................................ 9

Dr. Jacob Bornstein, Nahariya Hospital, Israel......................................................................... 10

Session II: Areas for Discovery .................................................................................................. 11

Dr. Libby Edwards, Southeast Vulvar Clinic, Charlotte, North Carolina ................................ 11

Discussion................................................................................................................................. 12

Session III: Basic Science Updates on Related Topics............................................................. 13

Dr. Karl B. Thor, Dynogen Pharmaceuticals and Duke University.......................................... 13

Dr. Michael Pezzone, University of Pittsburgh ........................................................................ 15

Dr. James Baraniuk, Georgetown University........................................................................... 16

Dr. Nina Bohm-Starke, Karolinska Instituet, Sweden.............................................................. 18

Discussion................................................................................................................................. 19

Dr. David Foster, University of Rochester ............................................................................... 20

Session IV: The Science of Pain................................................................................................ 21

Dr. Ursula Wesselmann, Johns Hopkins University................................................................. 21

Discussion................................................................................................................................. 22

Dr. Marshall Devor, Harvard University.................................................................................. 22

Dr. Jay Shah, NIH Clinical Center............................................................................................ 24

Dr. Richard Gracely, University of Michigan .......................................................................... 25

Session V: Evolving Therapies................................................................................................... 26

Dr. Anthony Visco, University of North Carolina.................................................................... 26

Dr. Peter Smith, University of Kansas...................................................................................... 27

Discussion................................................................................................................................. 28
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Session VI: Therapeutics............................................................................................................ 28

Dr. Gerald Gebhart, University of Iowa ................................................................................... 28

Dr. Don Manning, University of Virginia and Celgene Corporation....................................... 29

Dr. Keith Bley, NeurogesX, Inc................................................................................................ 31

Dr. Sophie Bergeron, Université du Québec á Montréal.......................................................... 32

Final Discussion .......................................................................................................................... 34

Planning Committee .................................................................................................................... 35
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Vulvodynia: Toward Understanding a Pain Syndrome

April 14-15, 2003

Introduction

The aims of this workshop were to present an overview of the science and epidemiology of 

vulvodynia and to elucidate the fundamental mechanisms of vulvodynia and related pain 

syndromes. The ultimate aim is thus to stimulate innovative research approaches to the study of 

vulvodynia and to develop clinical strategies for appropriate and evidence-based methods of 

alleviating vulvar pain.

Session I: Overview and Epidemiology

Dr. Maria Turner, National Cancer Institute (NCI) 

Dr. Turner opened the workshop by presenting an overview of vulvodynia, focusing on those 

topics that were discussed at the first Vulvodynia Workshop in 1997, including the 

recommendations that were made at the meeting and some of the advances that occurred in the 

field between 1997 and 2003.

Vulvodynia, as defined by the International Society of Study of Vulvar Diseases (ISSVD) in 

1993, is chronic vulvar discomfort characterized by the patient’s complaint of burning, stinging, 

irritation, and rawness. Commonly, women complained of pain in the vulvar vestibule. These 

symptoms have multiple causes. 

In 1997, very little knowledge existed regarding vulvodynia; what was known was based on 

clinical observations. At the first workshop, information was presented indicating that 

microscopic pathology studies of the vulva demonstrated very non-specific findings. 

Occasionally, lymphocytic infiltration surrounding the vestibular gland opening was noted, but at 

other times there was only a very small infiltration just below the dermal mucosa. In vulvodynia 

patients, the bacteria observed in the lower genital tract were abnormal, with a high prevalence 

of candida. A survey report from the National Vulvodynia Association showed that 30 percent 

of women with vulvodynia also had fibromyalgia.

Although the first workshop included presentations of pelvic neurophysiology and disorders of 

the pelvic floor, no information was presented on the epidemiology of vulvodynia because there 

was no information available at that time. A highlight of the workshop, however, was the 

recognition that vulvodynia is a chronic pain syndrome. Generalized pain mechanisms, 

especially those of visceral pain, such as altered central processing, could be maintained by 

stimulation of peripheral nerves. The genetics of pain were discussed, as was gender-specific 

pain perception. The myth that vulvodynia was solely psychosomatic was dispelled. 
Vulvodynia: Toward Understanding a Pain Syndrome

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Several research recommendations were made at the first workshop including the need for: an 

exact definition of vulvodynia, multicentered clinical trials, well-conducted epidemiological 

studies to identify those at risk for the vulvodynia, studies to explore the relationship of 

psychosexual history to the disorder, and an examination of the role of infections such as Herpes 

Simplex Virus (HSV), Human Papilloma Virus (HPV), and candida as initiators of vulvodynia. 

It was also recommended that basic scientists be stimulated to develop animal models for 

neuropathic conditions of the pelvic floor.

In 2003, clinicians and scientists were still having difficulty using standard terminology, 

although most accepted a definition that excluded the dermatoses and nerve damage. In the 

interval between the first and the current workshop, a population-based prevalence study was 

initiated and a preliminary report of some of the findings would be presented at this workshop. 

In addition, six other studies had been funded by the NICHD. 

Dr. Barbara Reed, University of Michigan

Dr. Reed, a discussant, remarked on research on vulvodynia—that is, where it is and where it 

should be. Half of all the vulvodynia-related publications were published since 1997. No longer 

was the disease thought to be psychological in origin. In the future, physician awareness of 

vulvodynia should increase so that women suffering from the disease would be diagnosed (and 

treated) in a timely fashion. Patients who currently had vulvodynia hoped that this workshop 

would lead to cures and treatments for the condition. However, one of their most urgent requests 

was to spread the word about vulvodynia so that women may receive the help that they need 

now. 

An e-mail survey was conducted with 3,000 women, ages 18 to 78, resulting in the response of 

1,025 women. One-half stated that they had pain with intercourse, and 28 percent said that they 

had pain at the introitus at some point in time. Of those, 8 percent stated that this pain had been 

felt within the six months prior to the survey, while 3 percent had had pain for more than three 

months. At the time of the survey, 1.7 percent had current pain that had lasted more than three 

months, the equivalent to 15 women in each family physician’s practice, and double that in each 

gynecology practice. This number represents more than 2.4 million women, when the 

information is extrapolated to the general population. 

Based on this survey, the average time from pain onset to diagnosis was 5.3 years and ranged 

from less than one to 29 years. About 50 percent of the women had seen more than two 

physicians, while 25 percent had seen four doctors; 80 percent of the patients had seen a 

gynecologist, and more than 50 percent had seen a family physician.

In addition, women with vulvodynia were not sexually averse, but were sexually active and 

interested, and were no more likely to have been physically or sexually abused. More than 

50 percent had had sexual intercourse in the year prior to the survey. 

This workshop was intended to provide a forum where the newest science could be discussed, 

ideas traded, and perceptions challenged. As what has been learned in the past six years was 
Vulvodynia: Toward Understanding a Pain Syndrome

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evaluated and the future research agenda was discussed, Dr. Reed urged participants to 

remember the women who have vulvodynia and what they have to say about this condition.

Dr. Bernard Harlow, Harvard University 

Dr. Harlow described NICHD-funded, population-based studies of vulvar dysesthesias. The goal 

of this research was to estimate the prevalence of these chronic, unexplained lower-genital-tract 

disorders, and to identify cases and match them to population-based controls to assess factors, 

such as perineal injuries, environmental irritants, abrasives, and other antecedent exposures to 

the first onset of genital symptoms. 

The prevalence study was conducted with access to the Massachusetts Town Books, a set of 

state-mandated annual census directories. Approximately 16,000 women from the general 

population are screened by a one-page, optically scannable questionnaire, with 450 subjects per 

month being accessed into the study. Participants are separated into groups of those who had 

past vulvar symptoms, those experiencing current vulvar symptoms, and those with no history of 

such symptoms. So far, 8,700 women have been screened, and 7,000 women were given the 

opportunity to participate in the first phase of the screening questionnaire. There has been an 

overall 67 percent response rate to this invitation to participate. Of all the women, 16 percent 

stated that, at some point in their lives, they had chronic burning pain on contact, or pain that was 

“knife-like” and sharp for three months or longer. When women with endometriosis, uterine 

fibroids, and polycystic ovary syndrome were removed from the calculations, 14 percent of 

women experienced a chronic vulvar pain disorder. Of this percentage, three-fourths had pain on 

contact, and one-fourth had burning or knife-like pain. The cumulative incidence was similar in 

African American and Caucasian women. Women who identified themselves as Hispanic were 

70 percent more likely to report a history of chronic vulvar pain (2l.4 percent) and Asian 

American women were somewhat less likely (10 percent).

Within the 16 percent prevalence estimate, 40 percent of the women never sought treatment. Of 

those who did seek treatment, 30 percent had to see five or more physicians prior to diagnosis, 

while 40 percent of those who sought treatment did not receive a diagnosis. Only 9 percent were 

diagnosed with a chronic vulvar pain disorder. Thus, women seeking medical care are forced to 

see several clinicians and often receive an inaccurate diagnosis. In the study so far, women who 

reported great pain or difficulty with first tampon use were six to seven times more likely to 

report a chronic vulvar pain disorder. Women with a history of burning or sharp-contact pain 

were much more likely to self-report recurring yeast infections, as well as bacterial vaginosis, 

when compared to women with no chronic pain. 

The case-controlled study was conducted by a telephone questionnaire administered to the 

women identified as having a current vulvar pain disorder in the prevalence study. Stringent 

criteria were used to classify the pain disorders and to avoid including women with pelvic pain. 

There was an excellent correlation of diagnosis as evaluated by phone and in actual physical 

examination of the subjects. Of those women selected as cases and evaluated clinically, 

80 percent were more likely than not to meet ISSVD criteria for vulvar dysesthesia. Cases were 

matched by age and community of residence to women with no history of vulvar pain, and a 

reference age was used for analysis. For instance, if vulvar pain in a 35-year-old subject began 
Vulvodynia: Toward Understanding a Pain Syndrome

4

at age 25, information regarding potential risk factors was collected from age 25 and prior years 

in both cases and controls. So far, the case-control study findings with respect to first tampon 

use replicated the findings from the screening questionnaire in the prevalence study. 

Interestingly, this finding of pain with first tampon use in the study was associated with 

childhood victimization prior to age 11. Women who never or rarely received support from their 

families were three times more likely to develop a vulvar pain disorder in adult life. Women 

who were physically harmed and lived in fear of physical abuse were five times more likely to 

develop a vulvar pain disorder. In particular, women who were harmed by a primary family 

member during childhood were much more likely to develop such a disorder when compared to 

those harmed by a non-family member. No strong association with sexual abuse and later vulvar 

pain was found. However, women who had been sexually abused and also lived in fear of 

further abuse were 2.6 times more likely to develop vulvar pain. This association was greatest in 

women who had been abused by a family member and was attenuated when both physical abuse 

and sexual abuse were analyzed, suggesting that the association with abuse was due mostly to 

physical abuse.

A two-fold increase in risk for vulvar disease occurred in women with symptoms of depression, 

when those symptoms occurred before the onset of vulvar pain. Furthermore, almost all of the 

association with major depression was noted in women who were never physically abused, while 

the impact of depression due to childhood physical abuse had no effect on vulvar dysesthesia 

later in life. Women who experienced pain and discomfort at the time of first tampon use were 

those most prone to developing a major depression antecedent to a chronic vulvar pain disorder.

There appeared to be only a 20 percent increase in the risk of vulvar pain disorder among those 

women using oral contraceptives for non-contraceptive reasons, such as for control of menstrual 

irregularities. Interestingly, women who had experienced pain at the time of first tampon use 

were not at increased risk for the development of vulvar pain as a consequence of oral 

contraceptive use. However, women who reported little or no pain with their first tampon use 

were at a substantially greater risk of developing vulvar dysesthesia as a consequence of oral 

contraceptive use. 

These findings suggested that there may be two etiological pathways leading to chronic vulvar 

pain: one pathway heralded by childhood abuse or pain and difficulty with first tampon use, as 

well as major depression; another through oral contraceptive use in women with no childhood 

victimization or problems with tampon use shortly after menarche.

Dr. Mary Margaret Chren, University of California, San Francisco 

Dr. Chren, a discussant, brought out that fact that Dr. Harlow had presented two studies. The 

first was a population-based, cross-sectional survey of 4,800 women to examine the prevalence 

of current or past vulvar discomfort, defined as burning or sharp pain on contact, and the second 

was a case-controlled study to examine exposure associated with vulvodynia, when the outcome 

was presumed vulvodynia. The cases had current discomfort, and the controls were women of 

the same age, race, and education, but without discomfort. Exposures were defined as occurring 

before the onset of discomfort and included: family support in childhood, physical and sexual 

abuse in childhood, and oral contraception use. In the prevalence study, 12 percent of women 
Vulvodynia: Toward Understanding a Pain Syndrome

5

overall reported current or past vulvar pain on contact, and 3 percent reported current or past 

vulvar burning or knife-like pain lasting at least three months, for a total of around 16 percent. 

The prevalence of current or past discomfort was consistent among ethnic subgroups, and there 

was a strong association between current or past discomfort and great pain on first tampon use. 

She added that Dr. Harlow was to be commended for this study. 

She felt, however, that it was essential to note that these were preliminary data and that the 

studies were ongoing. The 16 percent included women who had dermatitis, infection, or pain on 

contact from a myriad of causes in addition to vulvodynia. The measures used in these studies 

were excellent because Dr. Harlow and colleagues took into consideration the temporal 

relationship of the exposure to the onset of the symptoms. They made certain that the exposure 

was prior to the onset of the risk for the development of the vulvar pain. In measuring the 

variables, depression was defined by valid instruments. 

Despite this attention to measures, questions remained. Although the survey instruments were 

valid among less common ethnic groups, were these women as likely to respond as others in 

more common groups? Was the definition of the cases valid? Were non-responders different 

from those who responded, and if so, how? Either they were women without vulvar pain and, 

thus, did not take the time to answer the questionnaire, or they were women with extreme vulvar 

pain who were so upset that they were offended by the survey. There was also recall bias in 

exposure ascertainment. Cases may be more motivated to remember exposures. Interviewers 

may have probed more carefully with cases than with controls. 

There was an existing framework for this study based on previous data regarding childhood 

victimization and oral contraception, and these a priori hypotheses need to be carefully 

examined. This study was the beginning of establishing the syndrome of vulvodynia more fully. 

Additional studies were needed to address etiology and pathophysiology, natural history, and 

course of treatments. Rigorous outcomes and disease statuses were also needed. This situation 

was problematic for pain syndromes and for vulvodynia in particular because the condition was 

defined by patient experience. Because there were no specific laboratory tests, accurate 

measurements of pain and how pain affects the patient were needed.

Dr. Chren reported results from a study of the experiences and perceptions of 280 women with 

vulvar conditions. In this study, precise definitions for vulvar diagnoses were used, and quality 

of life was measured using Skindex (-29), a valid dermatologic quality-of-life measure. Of the 

280 women, 36 percent had either generalized or localized vulvodynia. In addition, 11 percent 

had lichen sclerosis, 11 percent had lichen simplex chronicus, 6 percent had lichen planus, and 

6 percent had candidiasis, while the remainder had less common vulvar conditions, such as 

papillomatosis. The quality of life of women with all vulvar conditions was worse than that of 

patients with eczematous dermatitis (a highly symptomatic disorder) or acne vulgaris (a 

condition that often affects appearance). Thus, these women’s vulvar disorders significantly 

affected their quality of life. Compared to women with other vulvar disorders, women with 

vulvodynia were more likely to be Caucasian, more likely to report a history of depression or 

anxiety, and had worse quality of life.
Vulvodynia: Toward Understanding a Pain Syndrome

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In the study, two-thirds of those with vulvodynia said that the disorder prevented them from 

having sexual intercourse. It was determined that vulvodynia affected women’s quality of life in 

unique ways that were not measured by standard psychometric instruments. 

In summary, the research agenda for vulvodynia must include: agreement on a precise clinical 

definition for research purposes to facilitate communication; basic and epidemiologic studies of 

which Dr. Harlow’s was an excellent example; patient-based studies of natural history and 

course of treatment; measurement of burden of disease; and specific measures of the effects of 

vulvodynia on the quality of life.

Dr. Elizabeth G. Stewart, Harvard University

Dr. Stewart discussed current therapies by first stating that, until there was a clear etiology of 

vulvar pain, treatment would be varied. The field was hampered by poor definition and poor 

description of what constituted improvement. Treatments would only be empirical until a clear 

etiology was discovered. Currently, there were 26 different modalities for vulvar vestibulitis 

reported in the medical literature, with little evidence from well-designed studies to support 

them. The treatment of generalized dysesthesia, or vulvodynia, and localized dysesthesia, or 

vestibulitis, was challenging. There was a clinical overlap in these pain syndromes, which made 

their treatment even more challenging. Those who treat pain recognized that pain syndromes 

require a multimodal approach. 

In general, treatment began with an accurate diagnosis; patient education was also important. By 

first giving a concrete label for the pain problem, the physician reassured the patient. Pain 

theories, pathophysiology, and proposed treatment plans should all be explained. Referral to 

counseling and support groups was vital, as was psychosocial help to overcome the learned 

response to pain. Psychosexual help for women who have pain with intercourse was also 

essential. In addition, the treatment of depression was a mainstay of any pain program.

Triggers to pain needed to be treated as an adjunct to therapy. The elimination of candida 

infection was important, however, antifungals alone were insufficient treatment of vulvodynia. 

Physicians must recognize that most women with vulvar pain disorders stayed sexually active 

despite lack of arousal, poor lubrication, and incredible pain. Many women treated themselves 

and often engaged in deleterious practices. Open communication between a patient and her 

partner was also important and should include a discussion of alternatives to vaginal intercourse.

Specific treatment modalities included topical estrogens, delivered as a cream applied to the 

vulva or vestibule, or by intravaginal rings or tablets. Estrogen used in this manner was 

completely unstudied, even though it was often used on a daily basis until pain was significantly 

improved. It may work through its effect on epithelial maturation, but it also inhibited the 

production of inflammatory cytokines. Estrogens were a component of oral contraceptives 

implicated in the etiology of vestibulitis. 

Tricyclic antidepressants were widely used in pain therapy, in general, and were effective 

separately from their antidepressant action. They were the treatment of choice for women with 

generalized dysesthesia, although only one small, published study documented this phenomenon. 
Vulvodynia: Toward Understanding a Pain Syndrome

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Amitriptyline was the prototype tricyclic and was given at 10 mg to 100 mg doses. Side effects 

made the tricyclic antidepressants difficult for patients to take, thus switching to different 

members of the family could be helpful. Localized dysesthesia had shown improvement with up 

to 75 mg of amitriptyline in one small study. Many physicians prescribed up to 150 to 200 mg of 

this drug for three months. Serotonin reuptake drugs were very limited in their ability to 

alleviate pain, although currently utilized dosages may not be high enough to do so. The side 

effects of these drugs limited their use significantly, however.

Veniaflaxene was reported to be effective in three patients with generalized dysesthesia. It was 

used in the treatment of localized dysesthesia in a dose of 200 mg. Gabapentin, an 

anticonvulsant drug approved for post-herpetic neuralgia and diabetic neuropathy was widely 

used in dosages of 1,000 mg for both generalized and localized dysesthesia. Some physicians 

prescribed 3,600 mg for three months before they declared a treatment failure. Other 

antiepileptic drugs, such as valproic acid, had been studied as therapy for vulvar pain as well.

Topical 0.2-percent nitroglycerin cream, a cytokine antagonist, used in a pilot study had been 

reported to show some improvement in vulvar pain. Anecdotal evidence suggested that 

antihistamines are not effective, and cromolyn had also been shown to be ineffective. Capsaicin 

and imiquimod may be helpful, but they had irritant properties. Medium- and high-potency 

steroids were reported to be helpful in some cases; however, evidence for this response was 

limited. Most clinicians stated that treatment with corticosteroids was disappointing, unless there 

was an inflammatory dermatosis present.

The current focus of therapeutics was in the combination of a centrally acting drug with a topical 

anesthetic, as in the case of topical lidocaine combined with tricylic antidepressants. An openlabel study had shown significant improvement, and a placebo-controlled study will be started 

soon.

In 1999, at the ISSVD meeting, reports from a single center suggested that interferon was just a 

little bit better than placebo in treating pain, but it was still widely used. One recent study 

suggested that the inability to product endogenous interferon might be a factor in vulvar pain. 

Women who practiced biofeedback for 16 weeks to diminish hypertonicity in their pelvic floor 

muscles had decreased pain on follow up. Many women liked this treatment because there were 

very few side effects. Physical therapy showed modest improvement in symptoms of both 

generalized and localized vulvar dysesthesia. The physical therapy aimed to alleviate the vulvar 

pain referred from the ligaments and joints in the spine and pelvis. One pilot study also showed 

that acupuncture improved the quality of life in women with vulvodynia. 

There were no reported controlled studies of low oxalate diet on vulvar pain disorders. (Editors’ 

note: a study is currently being conducted at the University of Medicine and Dentistry of New 

Jersey, in New Brunswick, New Jersey.) Oxalate may be an irritant to the vulvar vestibule in the 

same way that acidic foods are an irritant to the bladder in patients with interstitial cystitis.

By far the most controversial therapy for vulvar vestibulitis was surgical vestibulectomy. 

Surgery was criticized because of a lack of a clear pathophysiology for vulvar pain. Other types 
Vulvodynia: Toward Understanding a Pain Syndrome

8

of pain were not treated surgically. In addition, concerns were expressed regarding cosmetic 

results and the effect on body image. However, neural hyperplasia occurred in vestibulitis, and 

excision of neural hyperplasia was effective in relieving pain. Careful selection of surgical 

patients was essential; the most important rationale for surgery should be the failure of other 

treatment regimens.

Although it was difficult to compare surgery that utilized different techniques, three published 

case series revealed a success rate of 80 percent to 89 percent. Predictors of surgical failure 

included primary vestibulitis, diffuse vulvar pain, urinary symptoms, and muscle hypertonicity. 

Nevertheless, surgical treatment had a successful record for improvement of symptomatology. 

Reportedly, pain was significantly improved by surgery in combination with behavior treatment 

techniques. Several pain centers in the United States and Europe have performed decompression 

of the pudendal nerve, as well as nerve blocks.

In summary, there was a need for careful controlled trials of various therapeutic modalities. 

Local cytokine antagonists showed promise, as did modulation of central sensitization of neuroinflammatory pain in localized dysesthesia. There was recognition that pain itself needed to be 

treated. The meaning of pain to an individual women and its impact on relationships should also 

be fully understood.

Dr. Daniel Handel, NIH Clinical Center

Dr. Handel, a discussant, noted that vulvodynia was a burning or combination of a dysesthetic 

sensation anywhere from the mons to the anus that caused physical, sexual, and psychological 

distress. There were commonly mixed components and the true incidence was unknown, 

although it was more common than previously thought. Dr. Stewart clearly stated that there 

were multiple etiologies. Thus, there was no unifying concept in terms of management. A 

recent concept was that neuropathic pain was a primary causation. The pain can be one-sided or 

bilateral, sporadic or constant. The patient often reported a swelling sensation, and paraesthesias 

were noted. Sometimes there was a mix of paraesthesia with other sensations. Often there were 

periods of time that were symptom free. The history of a patient may reveal surgery or injury, 

especially sports injury. The physical history should include information regarding possible 

back injury or surgery to treat such problems, such as herniated disc, low lumbar disorder, 

possible arthritis of the hips or pelvis, and spinal stenosis. The type of physical stresses the 

patient endured at work or leisure must be explored.

The diagnosis was one of exclusion and, as had been mentioned, the patient often saw multiple 

physicians. During the physical examination, a work up for vaginal infection and irritation must 

be done. Culposcopy was indicated to evaluate any local lesions and appropriate biopsies should 

be obtained. Urine culture and spinal imaging studies should also be performed when indicated.

Many women with vulvodynia or vestibulitis experienced loss of hope, which led to 

psychological, emotional, and spiritual issues. The sexual sense of self provides another 

dimension to the issues faced by these patients. The fear of loss of self, the feeling that “I don’t 

know who I used to be,” and the issue of pain without physical findings cannot be underplayed.
Vulvodynia: Toward Understanding a Pain Syndrome

9

There were few people dedicated to this disorder, but they needed to be the professionals 

consulted by patients. They knew the literature and were aware of the treatments that might be 

helpful.

Helpful treatments included physical therapy, although it was not known if this treated the 

disorder, or if the individual’s abnormal response to it treated the disorder. Surface 

electromyographic (EMG) assisted pelvic floor rehabilitation was one therapeutic approach. The 

elimination of contact irritants was also important and included panty hose, synthetic underwear, 

jeans, swimsuits, scented soap, bubble baths, wash clothes, feminine sprays, deodorants, and 

powders.

Multiple studies showed tricyclic antidepressants to be helpful. There were several different 

tricyclics that offered help, but it was important to avoid their side effects. Anticonvulsants had 

a mixed history in terms of treating pain. The older ones were often difficult for patients to 

tolerate, but newer ones had far fewer side effects; however, the efficacy of these agents for 

vulvodynia needed further research. 

It was often helpful to combine a therapeutic central approach with a peripheral approach. At the 

NIH Clinical Center, the approach was to think about a patient’s primary symptoms and let these 

symptoms guide therapy. Nitroglycerin cream prior to intercourse was one such approach, and 

there was a large study under way to confirm its usefulness. Opioids should be considered for 

pain, but they should not be given until a thorough evaluation was done and the diagnosis made. 

The physician should know why the opioid was chosen and should have specific and measurable 

goals for therapy.

Pain clinics willing to offer multimodal sex therapy, in addition to providing relief of pain, were 

very helpful in the treatment of vulvar pain. Vulvodynia was a disorder more common than

thought previously; however, its true incidence was still unknown. It was most likely that 

research would reveal subpopulations in which various types of symptoms existed, but these 

subpopulations needed to be identified. Until there was a unifying concept of etiology, at least 

for subpopulations, therapy should be guided by determining the most troublesome symptom for 

the patient, and treating that symptom first.

Dr. Hope Haefner, University of Michigan

Dr. Haefner, a discussant, brought out alternative therapies for vulvar pain, many of which 

needed to be studied as to their efficacy. In 1997, there were more than 600 million visits to 

alternative therapeutic practitioners, a number higher than those to primary care physicians. 

More than $35 billion per year was spent on alternative treatments. Patients with vulvar pain 

often sought alternative therapies when they did not respond to conventional treatment. One 

study demonstrated that 96 percent of 26 patients with vulvar pain used at least one form of 

complementary health care product. Many of these products were found to contain steroids. The 

definition of alternative therapy was problematic because health care providers counsel their 

patients on a daily basis regarding diet, alcohol consumption, smoking, and physical activity, yet 

others considered these topics as complimentary or alternative medicine. Physical therapy and 

biofeedback for vulvodynia were also helpful. Are these alternative therapies?
Vulvodynia: Toward Understanding a Pain Syndrome

10

There were many therapies that could be studied for the treatment of vulvodynia, including 

hydrotherapy and acupuncture. Hydrotherapy was used in vulvar care, and ice packs were 

prescribed as well; patients indicated that these were helpful. Although acupuncture was 4,700 

years old, its use for the treatment of vulvodynia was new. A biological theory as to how 

acupuncture works was that it involved opioid peptides. A study of acupuncture points for 

vulvodynia treatment demonstrated that the points on the sacrum tend to be lateral, and that those

on the front of the body tend to be more central than those for other diseases. One study 

conducted by the National Vulvodynia Association showed that 35 percent of those treated with 

acupuncture had a positive therapeutic response. Other studies have not confirmed this finding. 

The use of pressure points in therapy should also be studied. Other alternative therapies that 

might be useful and, therefore, should be studied were: aromatherapy, guided imagery, healing 

touch, hypnosis, herbal medications, vitamin E (i.e., in promoting tissue regeneration and wound 

healing), massage therapy, meditation, yoga, and tai chi. Health care providers needed to be 

concerned about the quality and efficacy of alternative medicine. Because natural was not 

necessarily safer than synthetic chemicals, randomized trials were very much needed to evaluate 

alternative treatments for vulvar pain.

Dr. Jacob Bornstein, Nahariya Hospital, Israel

Dr. Bornstein, a discussant, mentioned that he had been involved in the treatment of vulvodynia 

since 1985. In his mind, the real question was: why did surgical treatment for vulvar vestibulitis 

have such a poor reputation? Not all surgery was successful, even though women were told that 

surgery was the end of the road. Some surgical techniques were inadequate or inappropriate. 

When it failed, there was a great disappointment for all. Why did surgery fail? One possible 

reason was because, in most patients, the sensitivity was localized to the base of the hymeneal 

ring, not the vestibule. 

To be done correctly, the recommended procedure should be done under general or regional 

anesthesia. The incision was made below and lateral to the urethral meatus and extended along 

the perineum to half the distance between the fourchette and the anus. The amount of tissue 

removed varied according to the surgeon, and there was currently little research on the 

appropriate amount of tissue to be excised. But, typically, about 5mm of mucosa and underlying 

stroma was removed. The vestibule was excised to the hymeneal ring and the tissue surrounding 

the meatus. If needed, the anterior vestibule was also excised. The vaginal mucosa was 

undermined for 1-2 cm, and then advanced and sutured to the skin. The vaginal epithelium was 

exteriorized, which created a result whereby the anterior vulva looked the same as prior to the 

surgery. The vaginal tissue was advanced to the perineum so that the mucosal skin scar was not 

at the introitus, thus avoiding future sensitivity in this area. The patient was hospitalized 

overnight and treated with ice packs, sitz baths, and analgesics for 10 days.

In most cases, complications were minimal. One more common long-term complication was 

Bartholin Duct Cysts. Persistent vestibular tenderness or even increased tenderness occurred in 

5 percent of patients and posed a serious problem.
Vulvodynia: Toward Understanding a Pain Syndrome

11

Did surgery work? A prospective randomized comparison of vestibuloplasty—that is, 

undercutting the vestibule without excising it—did not demonstrate relief of symptoms. 

However, perineoplasty worked. Analysis of the data was limited by a few problems: often, the 

criteria for success or resolution of symptoms were not mentioned, nor was there good follow-up 

information; further, surgical terminology and pain measurement were not standardized, nor was 

patient selection clear. 

Reported studies have demonstrated a 20 percent failure rate, in general. Studies with higher 

failure rates had methodological flaws. In a study conducted by his group, Dr. Bornstein 

reported that there were two groups of patients who failed to be helped by surgery: one group 

included women with primary pain on intercourse, and the second group included women who 

had constant pain in addition to dyspareunia. This latter subset should not undergo surgery 

because this treatment failed to help the pain in 50 percent of the patients.

Surgery was not recommended as first line therapy, but, rather, as part of a treatment program. 

In Dr. Bornstein’s program, pelvic floor biofeedback, low oxalate diet, calcium citrate 

supplementation, and estrogen cream application for oral contraceptive users was prescribed 

initially. 

A new direction in the surgical treatment of vestibulitis may come from a different approach. 

Five women operated on by Professor Peter Petros of Perth, Australia, for enterocele also had 

vulvar vestibulitis. The correction of the posterior wall defect in these cases cured the 

vestibulitis, which raises the possibility that releasing stress on the pudendal nerve relieved the 

pain.

Session II: Areas for Discovery

Dr. Libby Edwards, Southeast Vulvar Clinic, Charlotte, North Carolina

Dr. Edwards addressed Questions that Need Answers, which included: epidemiology; the 

division of vulvodynia into and the characterization of subsets; the possibility of multiple 

etiologies causing vulvar pain; and the controversy about the existence of inflammation in 

vestibulitis. Questions regarding the role of neuropathic pain, and the abnormalities of central or 

peripheral processing and the function of the pelvic floor (muscle and fascia support) were also 

discussed. And of course, the very major question of what treatments are effective was 

presented.

Some current epidemiologic studies revealed understandings about vulvodynia that were 

different from the accepted understandings of the past 10 to 15 years. Past ideas, perhaps, were 

wrong. For instance, past studies did not show an association with childhood sexual and 

physical abuse and vulvodynia, but today evidence of such an association was presented. Thus, 

additional studies were needed. Vulvodynia among African American women needed to be 

studied further, as well.
Vulvodynia: Toward Understanding a Pain Syndrome

12

The accurate definition of the disease was important, not only for epidemiological studies, but 

also for treatment protocols. The term vulvodynia was a description only. The issues of 

population subsets also needed to be addressed, especially in determining those individuals for 

whom vestibulectomy was appropriate. The strictest definition of vestibulitis was that the pain 

was only located in the vestibule, and that it was only elicited by touch. Dysesthetic vulvodynia, 

on the other hand, was generalized pain, migratory pain, or pain that sometimes extended beyond 

the vestibule. Touch, in this case, did not produce pain. While these strict definitions were ones 

that many physicians and scientists subscribed to, they did not always hold up in the clinical 

setting. Thus, the question remained—were these distinct, easily separable subset definitions 

that could be clearly divided in clinical settings, or did vulvar pain exist on a spectrum between 

the two? Individuals may have aspects of both vestibulitis and dysesthetic vulvodynia, and 

perhaps, these conditions existed on a spectrum rather than occurring as easily and distinctly 

separate conditions. Also, perhaps other characteristics distinguished the subsets, such as age, 

estrogen status, or concomitant conditions, including fibromyalgia, irritable bowel syndrome, 

interstitial cystitis, back pain, or others, suggesting a central-processing abnormality. Could it be 

that longstanding vestibulitis tended to worsen and generalize into dysesthetic vulvodynia?

Another important question was whether or not vulvodynia was associated with inflammation. 

What was the meaning of increased numbers of white blood cells in vaginal secretions, as some 

noted, and increased inflammatory mediators in tissue of women with vestibulitis? Were these 

signs of inflammation due to tissue damage, or were they neurogenic inflammation? The pain of 

vulvodynia resembled neuropathic pain, and it often responded to therapy used for neuropathic 

pain in other areas of the body. If the vulvar pain was due to neuropathic pain, it needed to be 

characterized. For instance, was it pudendal neuralgia? Was it a complex pain syndrome? Was 

it due to altered central or peripheral processing, or could it be due to either? What was the role 

of pelvic floor dysfunction? Women with pelvic floor dysfunction had increased resting muscle 

tension, as shown by surface EMG measurements; they also had poor muscle strength. If 

abnormal pelvic floor anatomy was associated with vulvodynia, was it due to weakness of the 

increased tension? Why did strengthening exercises relieve pain?

Finally, the most important question was how to treat vulvodynia effectively. How can the pain 

be controlled? Could this condition be cured, as gynecologists often expected, or controlled, as 

dermatologists often expected? Placebo-controlled clinical trials were needed to determine what 

treatment(s) was successful.

Those treating vulvodynia could begin to find answers to these questions if they had better 

definitions, if they really tracked their patients in their offices, and if multicenter, standardized 

protocols were developed.

Discussion

Various participants raised a number of questions regarding the role of pelvic floor disorders in 

vulvar pain. Could laxity of the pelvic floor cause nerve stretching and, thus, cause pain? One 

participant pointed out that constant irritation would increase the area of pain through 

convergence and divergence of sensation. There was also discussion of the fact that there may 

be a continuum of pain and not two distinct entities of disease because symptoms overlapped. 
Vulvodynia: Toward Understanding a Pain Syndrome

13

Those present noted that there was a wide variety of treatments not related to underlying 

mechanisms of disease, even though there were solid concepts of the cause of chronic pain 

reported in the literature. In dealing with pain, it was essential to know where the pain was 

coming from. A simple diagnostic test, using infiltration of skin with a local anesthetic, would 

determine if there were sensitized nociceptors in vulvar skin. Participants mentioned two studies 

that did use local anesthetics, and these substances did seem to be helpful in relieving pain. 

Surgery was also based on the concept of eliminating abnormalities of the sensory nerve endings, 

and it did appear to be successful in many situations. 

Session III: Basic Science Updates on Related Topics

Dr. Karl B. Thor, Dynogen Pharmaceuticals and Duke University

Dr. Thor discussed a paper titled Neuroanatomy of the Pelvic Floor in Human, Monkey, and Rat. 

His collaborators in these studies were: Matthew Barber of the Cleveland Clinic; Kim Coates, 

Lisa Pierce, and Michelle Reyes of Scott & White Clinic; and Paul Dolber and Ron Bremer at 

Duke University. In vulvodynia, there was obviously nerve involvement in pain. Dr. Glazer 

indicated that vulvar pain could produce spasm of the levator ani muscle, which raised the 

following questions: could levator ani nerve damage produce spasm and, thus, pain in the 

vestibule and vulva, and might pelvic organ prolapse possibly be involved in vulvodynia? A 

hypothesis of the etiology of pelvic floor prolapse was that childbirth produced a crush injury of 

the levator ani nerve and, thus, eventually caused pelvic floor prolapse.

Classically, textbooks stated that the vulva (external genitalia and perineal skin) was innervated 

by the pudendal nerve, while the pelvic nerve innervated the vagina and the cervix. However, 

the pelvic floor innervation was poorly studied. Present studies were conducted to find the 

innervation of the pubococcygeus and ileococcygeus muscles. Prior to these studies, this 

innervation was described in the textbooks as originating from “sacral spinal roots,” which was 

nebulous, and the pudendal nerve. Glazer’s studies demonstrated this was not the case; instead, 

the pudendal nerve only innervated the rhabdosphincter muscle.

The pelvic floor consisted of the coccygeus, iliococcygeus, and pubococcygeus muscles as the 

primary muscles, while the smaller puborectalis muscle lied most medially. Dr. Thor’s group 

conducted a large number of nerve dissections in 13 human cadavers. Nerve biopsies were 

evaluated to ascertain that nerves were studied and not connective tissue. The nerve that they 

traced into the levator ani muscles, which they called the levator ani nerve, received 

contributions from the S3, S4, and/or S5 roots. In some cadaver specimens, the S5 root had its 

own pathway to innervate the puborectalis muscle. Importantly, the path of the levator ani nerve 

passed within 5 mm of the ischial spine. Thus, the levator ani nerve was susceptible to damage 

during suspension surgery for pelvic organ prolapse, or by a fetal head passing through the birth 

canal. 

Because the levator ani nerve was an intrapelvic nerve, it was in a position to be preferentially 

stimulated when a St. Mark’s electrode was inserted into the rectum. Furthermore, because the 
Vulvodynia: Toward Understanding a Pain Syndrome

14

levator ani nerve was so close to the ischial spine, it was likely that this nerve was also 

preferentially anesthetized at the time of pudendal nerve block during childbirth. 

In contrast, the pudendal nerve was an extrapelvic nerve. It quickly exited the pelvis, wrapped 

around ischial rectal fossa, entered the pudendal canal, and provided innervation to the external 

genitalia, the urethral sphincter, the anal sphincter, and the external genitalia. The branch that 

innervated the vulva and vestibule was very superficial, while the branch that innervated the 

clitoris was deeper. Thus, there was the possibility of trauma to the vulvar branch during 

bicycling and horseback riding, which could lead to neuropathy.

The levator ani nerve was also studied in rats and squirrel monkeys as model animals. The nerve 

in these species was composed of large motor axons and IA primary afferent fibers 10 microns or 

larger in diameter. These large fibers were not seen in the pudendal nerve. Cholinesterase 

staining revealed a single motor endplate at the midpoint of both the iliococcygeus and the 

pubodoccygeus muscles. Selective neurectomies showed that cutting the levator ani nerves 

produced significantly decreased levator ani muscle weight and myofiber diameter, while cutting 

the pudendal nerve did not.

Tracing studies with cholera toxin B (CTB) injected into the levator ani muscles demonstrated 

about 400-500 motor neurons, mostly in the S1-S2 segments. Their size distribution was 

bimodal—large, presumably alpha neurons and small gamma motor neurons. The neurons were 

diffusely organized and had a dendritic arbor that connected the longitudinal cell column in the 

ventral horn.

CTB-labeled primary afferent terminals were found just medial to the central canal in an area 

called medial lamina VI. Special stains (RT97 for neurofilaments found only in large primary 

afferent fibers, and IB4 and CGRP staining for small nociceptors) were used to determine that 

putative nociceptor neurons in the dorsal root ganglia innervated the levator ani muscles. About 

40 percent of the primary afferent neurons labeled by CTB were small peptidergic neurons, 

which should project terminals to the superficial dorsal horn. However, there was little CTB 

terminal staining in this area, attributed to a problem with technique.

In summary, the levator ani muscles were innervated by the levator ani nerve, while no evidence 

of innervation by the pudendal nerve could be found. The levator ani motor neurons were 

diffusely distributed in the sacral ventral horn, while the pudendal motor neurons were 

concentrated in Onuf’s nucleus. However, there was a great deal of overlap between the 

dendrites of levator ani motor neurons and pudendal motor neurons, and both nerves contained 

primary afferent fibers that projected into the sacral spinal cord. Thus, there was great potential 

for interactions between both the sensory and motor nerve fibers that controlled the levator ani 

muscle, the rhabdosphincters, the vulva, and the vestibule. These interactions could be 

physiological and/or pathological.
Vulvodynia: Toward Understanding a Pain Syndrome

15

Dr. Michael Pezzone, University of Pittsburgh

Dr. Pezzone discussed the function and innervation of the pelvic viscera and their striated 

sphincters, the pelvic organ reflexes, and the cross-talk between them. There was an overlap of 

chronic pain disorders, just as there was an overlap in vulvodynia. 

The most important function of the pelvic floor structures was support of the pelvic viscera, 

important to humans because of erect posture. The pelvic floor structures also functioned in 

urination and defecation. Other functions of the pelvic floor were related to sexual functioning 

and childbirth.

There were two components of innervation: autonomic innervation, with sympathetic and 

parasympathetic components; and somatic innervation. 

Sympathetic nerves originated in the thoracolumbar segments of the spinal cord, while the 

parasympathetic came from the sacral components of the spinal cord. The pudendal nerve 

originated in the sacral area. There was great potential for neural cross-talk because these nerves 

converged in similar areas in the spinal cord. Local reflexes occurred in the sacral spinal cord 

and were termed segmental reflexes because they were localized to the cord in the segments 

where afferent and efferent inputs converged. These reflexes were important for postural control 

of the pelvic floor. A polysynaptic pathway was activated by muscle stretch due to gravity and 

position, and this produced a reflex contraction, keeping the organs in place. This reflex was 

mediated by slow twitch muscles, which were continuously active. Fast-twitch muscles were 

activated during a cough or sneeze and, thus, further strengthened the pelvic floor muscles to 

prevent incontinence in a supra-segmental reflex arc involving the brainstem.

Neural cross-talk occurred when afferent activation of one organ influenced efferent output to 

another. (Afferent signals were conducted away from an organ; efferent signals were conducted 

from a central area to an organ.)

The pelvic and pudendal afferents overlapped in the spinal cord allowing integration of 

parasympathetic and somatic motor activity. The cross-talk occurred under normal conditions 

and was necessary for sexual, bladder, and bowel function. They were mediated by a 

convergence of sensory pathways in the spinal cord and could be altered by disease or injury. 

Some of these reflexes included: bulbocavernous, vesical-anorectal, anal, anal-vesical, and 

vesicolevator. 

Chronic pelvic pain disorders included those affecting the pelvis (i.e., irritable bowel syndrome 

and interstitial cystitis) and those affecting the pelvic floor (i.e., vulvodynia, urethral syndrome, 

prostatodynia, and orchialgia). Between 40 percent and 60 percent of persons with irritable 

bowel syndrome had interstitial cystitis, 38 percent of patients with interstitial cystitis had 

irritable bowel syndrome, and 26 percent of those with interstitial cystitis had vulvodynia, which 

suggested a common predisposition, a shared etiologic factor, or possible cross-sensitization via 

neural cross talk. Some mechanisms for pelvic organ cross sensitization were dichotomizing or 

shared C-fibers, afferent-afferent interactions, sympathetic reflexes, extra spinal reflexes via prevertebral ganglia and sphincteric interactions.
Vulvodynia: Toward Understanding a Pain Syndrome

16

Studies in rats showed that, when the bladder emptied during micturition, distal bowel 

contractions were inhibited. When an animal urinated, phasic firing of the urethral and anal 

sphincters occurred simultaneously, along with tonic contraction of the abdominal muscles. 

Conversely, when the colon was distended, the bladder and urethral sphincter were inhibited. 

In a series of experiments using a rat model, prior injury to the bladder epithelium caused 

bladder irritation (e.g., acute cystitis) when physiological doses of potassium were infused. 

During acute cystitis, colorectal distension produced lowered sensory thresholds or bladder-tobowel cross-sensitization. Likewise, when the colon was irritated acutely to cause colitis, the 

bladder contracted more frequently and exhibited signs of acute irritation.

When chronic colitis was induced in these animals, bladder capacity decreased, while bladder 

contraction frequency increased. Microscopic studies of these animals demonstrated evidence of 

mast cell hyperplasia, suggesting the development of neurogenic cystitis. These studies also 

indicated the presence of a chronic cross-sensitization process. Further experiments suggested 

that the chronic irritation led to the production of neurotrophic factors that caused nerve growth, 

mast cell recruitment, and neurogenic inflammation.

The frequent overlap of irritable bowel syndrome, interstitial cystitis, vulvodynia, and other 

chronic pelvic pain disorders may be indicative of aberrant neuronal interactions or reflexes, 

such that the irritation of one organ led to co-sensitization of others. With continued irritation, 

neurotrophic factors produced by both smooth muscles and sensory neurons may influence 

neurite outgrowth and axonal sprouting, which could lead to motor and sensory changes in target 

organs.

Dr. James Baraniuk, Georgetown University

Dr. Baraniuk asked: What is neurogenic inflammation? He noted that this concept needed 

revision because stimulation of nociceptive nerves did not cause immediate cellular infiltration

(i.e., inflammation). 

Different types of injury stimulated specific types of non-myelinated Type-C fibers. These 

neurons released neurotransmitters that caused tissue reactions, such as swelling, redness, or 

glandular secretion. Previously, it was thought that there was only one type of C neuron, and 

that vasodilation was the epitome of the axon response. Now scientists recognized a number of 

functional subtypes. About 5 percent were histamine H1 receptor “itch” nerves, 14 percent were 

heat sensitive and may express capsaicin/vanilloid receptors, 9 percent were heat plus histamine 

sensitive, 51 percent were mechanicothermal nerves, while the remaining 22 percent had 

undiscovered sensitivities. 

In rats, mice, and most likely humans, there were two distinct sets of Type-C neurons based on 

neurotransmitters. The first group contained neuropeptides, such as Substance P, calcitonin 

gene-related peptide (CGRP), and probably others. The second was non-peptinergic and 

contained the IB4-lectin. These nerves synapsed in spinal cord laminae 1 and 2, and some in 

lamina 6. The secondary relay interneurons crossed to the opposite spinothalamic tract to 

synapse in the thalamus. From there, stimuli were sent to various other systems to generate the 
Vulvodynia: Toward Understanding a Pain Syndrome

17

perceptions of itch, dull, aching pain, heat, and mechanical stimulation. There were significant 

links to the limbic system where these inputs affected emotion and memory responses, as well as 

brainstem autonomic centers to recruit reflexes in response to the nociceptive stimuli.

The itch nerves were the slowest conducting nerves in the body and innervated large areas of 

skin. They produced large “flare” (redness) or vasodilatation reactions. The erythema was 

caused by CGRP. Itch neurons were unique because they had distinct dorsal horn, lateral 

spinalthalamic, and thalamic pathways separate from those for pain and temperature. The itch 

pathway was stimulated by mast cell degranulation and release of histamine that acted on 

H1 receptors of the itch neurons. The peripheral axon response for this neural population was 

the flare.

CGRP caused slow onset, but long-lasting erythema. This peptide, 37 amino acids long, had two 

forms, α and β, which differed by three amino acids. CGRP, amylin, and adrenomedullin were 

in the same peptide family. CGRP Type 1 and Type 2 receptors stimulated adenyl cyclase in 

endothelial and vascular smooth muscle cells to cause potent vasodilation. CGRP accentuated 

the effects of other mediations that increased blood flow and endothelium-mediated plasma 

extravasation.

Vanilloid receptor-bearing neurons responded to heat, acid, and capsaicin. Capsaicin, the spicy 

essence of chili peppers, stimulated such extensive neurogenic inflammation that blisters like 

third-degree burns formed. Fortunately, most individuals were not exposed to this type of 

nociceptive stimulation. The neuron receptors were found in small diameter, non-myelinated 

Type-C neurons and responded to mechanical, moderate thermal stimuli, capsaicin, and related 

polyunsaturated fats, and to a pH less than six.

The nature of the axon response generated when Type-C neurons were depolarized and released 

their neurotransmitters depended upon combination of transmitters, distributions of their 

receptors on cells in the immediate area, the presence of proteases and other degrading enzymes, 

and the volume within which the neurotransmitters can diffuse. CGRP vasodilatory responses 

depended on the presence of both blood vessels and CGRP receptors in the region of the 

neurotransmitter’s release. Substance P release may generate many effects, including glandular 

secretion, vascular permeability, and, in inflammation, activation of inflammatory cells and 

increased chemoattraction of these cells.

Substance P was reported to degranulate mast cells, which appeared to occur in some rodent 

models, but had not been physiologically demonstrated in humans. One problem was that high 

doses of Substance P were often used to induce degranulation. This may occur by Substance Pspecific neurokinin-1 receptors. However, a Substance P mimetic synthesized with the highly 

positively charged N-terminal attached to a long chain hydrophobic alkane was equally potent at 

degranulating mast cells. This suggested that, in high concentrations, Substance P 

nonspecifically activated mast cell membranes or some membrane protein, to lead to 

anaphylactoid (anaphylaxis-like) mast cell mediator release. 

Populations of thinly myelinated Aδ fibers rapidly transmitted short-lived intense pain (i.e., first 

pain) sensations, pin-prick (i.e., sharp/dull), and cold sensations. Large Aβ and other neurons 
Vulvodynia: Toward Understanding a Pain Syndrome

18

innervated specialized cutaneous sensory receptors to convey fine touch, proprioception, 

vibration, and other sensations. 

Neurogenic mechanisms likely contributed to chronic multisymptom illnesses, such as 

vulvodynia, chronic fatigue syndrome, fibromyalgia, irritable bowel syndrome, chronic low back 

pain, chronic non-migraine headache, and irritant rhinitis. The overlap was demonstrated by 

examining data from 81 healthy controls (C), seven otherwise healthy women with dyspareunia 

(C+D), 92 women with chronic fatigue syndrome (CFS), and 21 women with both chronic 

fatigue syndrome and dyspareunia (CFS+D). The prevalence of dyspareunia was 3 percent 

versus 19 percent in CFS. These women were in their 40s. Muscle spasms were reported in 7 

percent of C, 57 percent of C+D, 52 percent of CFS, and 95 percent of CFS+D. A similar 

distribution was found for “dry eyes” with 6 percent of C, 57 percent of C+D, 42 percent of CFS, 

and 71 percent of CFS+D. A different pattern was found for “fever” with 1 percent of C, 

0 percent of C+D, 16 percent of CFS, and 52 percent of CFS+D, and for irritable bowel 

syndrome (Rome I criteria) with 7 percent of C, 0 percent of C+D, 36 percent of CFS, and 

81 percent CFS+D. Subjects in the CFS+D group had general tenderness as tested by 

dolorimetry: 2.21 kg/cm2 for C, 1.71 for C+D, 1.49 for CFS, and 0.97 for CFS+D. The 

differences in prevalences between groups for each variable were highly statistically significant, 

suggesting potential causal relationships between the mechanisms responsible for each 

complaint. 

Neurogenic responses were protective responses. Unfortunately, prolonged or severe 

mechanical, thermal or chemical irritation caused excessive local axon responses with the 

consequence that there was a dysregulation of pain processing in the dorsal horn of the spinal 

cord. One hypothesis being examined was that this regulated pain processing led to an organspecific axon-response mediated syndrome, and total body central nervous system mediated 

syndromes of chronic pain and hyperalgesia.

Dr. Nina Bohm-Starke, Karolinska Instituet, Sweden

Dr. Bohm-Starke described studies of Vulvar Vestibulitis Syndrome (VVS) conducted by her 

research group. These focused on the pathophysiology of the vestibular mucosa and its 

innenervation and relationship to inflammation. The results of the studies showed indications of 

an ongoing neurogenic inflammation in the vestibular mucosa in women with VVS.

The vestibular mucosa was by definition visceral tissue deriving from the urogenital sinus 

endoderm, but it was considered to have a non-visceral innervation and thus, the sensations of 

touch, temperature, and pain were similar to sensations evoked in the skin. The very peripheral 

nerves were traveling beneath the basal membrane, penetrating the epithelium at various sites, 

usually ending with a knob. These were sensory nerves, primary afferent neurons. Further down 

in lamina propria there was a predominance of autonomic nerve fibers, mainly around blood 

vessels. 

The peripheral nerves in the mucosa were first surveyed by immunohistochemical methods using 

PGP 9.5, a general marker of neural tissue. Biopsies from the area around the ductal openings of 

the Bartholin ́s glands, the most sensitive vestibular area in most patients, showed significantly 
Vulvodynia: Toward Understanding a Pain Syndrome

19

more intraepithelial free nerve endings than in healthy control subjects. These intraepithelial 

nerves were mainly immuno-positive for CGRP, the most abundant neuropeptide in primary 

afferent nerves in skin. Holtzer considered CGRP to be the major mediator of vasodilatation in 

neurogenic inflammation. 

The observed erythema in the posterior vestibule in the patients could represent vasodilatation 

and increased blood flow. Therefore, Laser Doppler Perfusion Imaging (LDPI) was performed 

to evaluate the microcirculation in the tissue (Bohm-Starke et al, 2001). An area of 5x6 cm was 

scanned, including the whole vestibular mucosa in patients, and in healthy control subjects. The 

blood flow in a total number of 3,000 sites was measured. After perfusion analysis, the results 

showed that, in the patients, a gradual increase in blood flow was registered from the anterior to 

the posterior part of the vestibule. In healthy women, however, no differences in the regional 

blood flow was registered. Several researchers have shown that this increased blood flow could 

be consistent with a release of CGRP from normally mechano-insensitive C-nociceptors, which 

could cause vasodilatation and axon reflex flare even at very low level of activity, thereby 

indicating a neurogenic inflammatory response.

The somatosensory function of the vestibular mucosa was also investigated using standardized 

quantitative sensory tests. Perceptual and pain thresholds to mechanical and thermal stimuli 

were investigated in patients, and in healthy controls. The patients demonstrated a significant 

hypersensitivity to mechanical and thermal stimulation in the entire mucosa, compared to the 

control group. The difference was most pronounced in the posterior vestibule, which was in 

accordance with clinical findings. The somatosensory abnormalities found in women with VVS 

were psychophysical evidence of sensitization and/or increased innervation of thermo-receptors 

and nociceptors in the vestibular mucosa.

In summary, the clinical findings and results from several studies indicated ongoing neurogenic 

inflammation in the vestibular mucosa in women with VVS.

Discussion

It was pointed out that pain thresholds were related to the pain threshold of the most sensitive 

nerve fibers. Thus, the number of nociceptors did not necessarily make a tissue any more 

sensitive if the threshold was still the same. A participant stated that there was a sharp 

demarcation or border in evocable pain from vestibule to vagina. There was a place where pain, 

tenderness, and the allodynia stopped, suggesting a nerve boundary between the pudendal nerve 

and the vestibular nerve. This finding could mean that nociceptors, rather than neurogenic 

inflammation, as inflammation would spread throughout tissue without regard to nerve 

boundaries. However, because the pain was bilaterally symmetrical, it suggested that the pain 

was not due to nerve injury. Thus, there was uncertainty in terms of the interpretation of the 

findings. 

There was also an inquiry as to whether or not sensory nerve fibers crossed the midline. The 

answer was that studies showed the pudendal nerve was one of the few nerves that crossed the 

midline within the spinal cord. However, this was not shown to occur in the periphery. At the 

conclusion of this part of the discussion, participants agreed that it was important not to try to 
Vulvodynia: Toward Understanding a Pain Syndrome

20

explain the data too much, but to continue with further research. An additional question was 

raised as to whether a biopsy should be used as a diagnostic standard. Dr. Bohm-Starke 

indicated that this was not an appropriate topic for this point of the workshop.

Dr. David Foster, University of Rochester

Dr. Foster summarized a series of studies of surgical pathology reports in regard to the presence 

of inflammation in VVS. He pointed out that inflammatory infiltrate was not specific and varied 

from mild to severe, which was one reason many professionals thought the terminology should 

change form vulvar vestibulitis to vestibulodynia or vulvar dysesthesia. The pain of VVS was 

highly localized in front of the hymenal ring (the vulvar vestibule) and was absent to minimal in 

degree in the vagina.

Dr. Foster proposed that the differences observed in the vulvar vestibule contrasted to the tissues 

in the vagina and the external vulva tissues were related to their embryological origin. The 

external vulva had stratified squamous epithelium. The vestibule was derived form the 

urogenital sinus and showed remnants of the original transitional epithelium. There was close 

cell-to-cell communication between surface epithelium and the underlying connective tissue.

Then, Dr. Foster reported on a study conducted by his research team in which biopsies from the 

vulvar vestibule, obtained at vestibulectomy, and biopsies from subjects who needed the 

procedure for problems other than pain were matched by race and age. In the area just in front of 

the hymen, Il-1β and TNFα, factors central to inflammation, were increased in VVS subjects. A 

second study tested the idea that fibroblasts in the vestibule might have different immune 

responsiveness compared to fibroblasts in other areas of the genital tract. Biopsies of the 

vestibule and the external vulva were obtained, and fibroblast explants derived from these 

tissues. These biopsies were taken from areas anatomically about 1.5 cm apart. The explants 

were grown to confluence and were vimentin-positive (a marker for fibroblasts), while 

cytokeratin, α smooth muscle antibody, CD34, and CD45 were negative, indicating that they 

were fibroblasts. Compared to stimulated vulvar-derived fibroblasts, stimulated vestibularderived fibroblasts had a significantly higher density of CD40, a member of the TNFα receptor 

superfamily. The vestibular fibroblasts differentially produced elevated PGE2 following 

stimulation with gamma interferon and CD40 ligand compared to vulvar fibroblasts. PGE2 was 

involved in the phosphorylation of certain nerve channels and made them “leakier,” which 

suggested that the vestibular fibroblasts responded differently to inflammatory stimuli and may 

facilitate enhanced activity in neural pain fibers. Interestingly, in the control vestibular 

fibroblasts more PGE2 was produced compared to control external vulva fibroblasts, although to 

a lesser degree than VVS-associated fibroblasts. An enhanced PGE2 production in the vulvar 

vestibule may, in part, be constitutive. 

Dr. Foster then presented studies describing the role of genetics in VVS. Homozygosity of Il1RA (allele 2) was associated with a number of chronic inflammatory conditions, such as 

rheumatoid arthritis and ulcerative colitis. There appeared to be a higher level of Il-1β with 

respect to the interleukin 1 receptor antagonist in individuals with homozygosity to Il-1RA 

(allele 2). This imbalance was thought to increase the risk for inflammation. It was also felt that 

NFκB signal transduction was responsible for the elevated Il-1β levels in these individuals. In 

addition, six Melanotcortin-1 Receptor (MC1R) single-nucleotide polymorphisms (SNPs) were 
Vulvodynia: Toward Understanding a Pain Syndrome

21

found to exist in significantly higher proportion in women with VVS compared to controls. 

MC1R was the skin and mucosal receptor for melanocyte-stimulating hormone (αMSH), a 

13 amino acid polypeptide, and has significant anti-inflammatory and analgesic properties. A 

normally increased cyclic AMP activity is inhibited in individuals with the six MC1R SNPs. To 

test the hypothesis that these MC1R SNPs were associated with reduced αMSH activity and, 

thus, with increased risk for vestibulitis in conjunction with Il-1 receptor antagonist 

polymorphisms, 36 cases and 61 controls were studied. DNA was amplified by polymerase 

chain reaction (PCR) and analyzed by both gel electrophoresis and by direct sequencing. 

Supporting previous research, significant homozygosity for Il-1RA (allele 2) was found in VVSafflicted cases compared to pain-free controls. The six SNPs of MC1R of interest were also 

more commonly found in VVS cases than in controls. IL-1RA (allele 2) homozygosity 

combined with at least one of the MC1R SNPs of interest was associated with an additive risk 

for VVS.

The vestibule responded to inflammatory stimulation in a different manner than other areas of 

the female genital tract, and there may be both constitutive and genetic susceptibility risk for 

chronic pain in the vulvar vestibule.

Session IV: The Science of Pain

Dr. Ursula Wesselmann, Johns Hopkins University

Dr. Wesselmann discussed connections between visceral pain and vulvodynia using chronic nonmalignant pelvic pain as a model. Visceral pain affected about 15 percent of women of 

reproductive age and cost the U.S. health care system an estimated $881 million per year. The 

differential diagnosis of chronic pelvic pain included gynecologic, urologic, gastrointestinal, 

musculoskeletal, neurologic, and other causes. Dr. Wesselmann noted that, while there were a 

few better-defined pelvic pain syndromes, such as interstitial cystitis and dysmenorrhea, her 

interest was chronic pelvic pain that did not fit a defined pattern and for which conventional 

diagnostic tests were unrevealing. Thus, like in vulvodynia, it was difficult to set up clinical 

studies for lack of a case definition. The current working definition, put forth by the American 

College of Obstetricians and Gynecologists, defined chronic pelvic pain as “pelvic pain in the 

same location for at least six months.”

Dr. Wesselmann gave two experimental models to show the interplay between vulvodynia and 

visceral pain. One example was from basic science studies in an animal model in her lab; the 

other was from psychophysical studies in interstitial cystitis patients. In her study, Dr. 

Wesselmann inflamed the uteri of anesthetized rats and quantified their pain. Once they 

recovered from this pain, she inflamed their vaginas. She was able to demonstrate C fos 

expression in the spinal cord of rats that were sacrificed two hours later. C fos was expressed by 

sensory neurons as a response to painful stimuli. Inflaming the vagina alone caused C fos 

expression in the spinal cord segments L5 to S1. However, in rats in which the vagina was 

inflamed after recovery from previous inflammation of the uterus, C fos was expressed all the 

way up to T10, a much wider field, which demonstrated sensitization by the previous uterine 
Vulvodynia: Toward Understanding a Pain Syndrome

22

inflammation. Although unproven, this may explain why, after recovering from a pelvic 

inflammation, a subsequent vaginal infection could trigger a chronic pelvic pain syndrome.

The other study was a human study on interstitial cystitis, which was often associated with 

dyspareunia in women. The bladder received innervation from the lower thoracic and upper 

lumbar spinal cord, and it also received innervation from the sacral spinal cord. Dr. Wesselmann 

noted that she was interested in studying the areas of referred pain in these patients with 

interstitial cystitis. Visceral pain typically presented with two components: one was a deep 

visceral pain component, localized to the organ where the pain was generated; and the other was 

visceral pain referred to somatic and other visceral structures along dermatomes, which 

corresponded to the spinal cord segments where innervation of the viscera was derived from. In 

interstitial cystitis, pain was initiated in the bladder. One would expect referred pain over the 

lower back and also in the urogenital area. Using quantitative sensory testing, she assessed 

different nerve fiber properties in the urogenital area of patients with interstitial cystitis and in 

normal controls. She assessed temperature thresholds, as well as temperature-induced pain 

thresholds. Control women had very little sensation in the vagina to start with. Their thresholds 

for both heat and heat pain detection were between 49 and 50 degrees Celsius. These controls 

usually did not sense cold pain even at 8 degrees Celsius. In contrast, the patients with 

interstitial cystitis had altered sensation to temperature stimuli and, in several patients, the point 

at which they sensed the sensation and when it became painful were rather similar. Only one of 

these patients had a diagnosis of vulvodynia. Some of the others had dyspareunia, without quite 

fulfilling the criteria for vulvar vestibulitis or vulvar dysesthesia. Dr. Wesselmann added that it 

would be interesting to see if these patients, later on, developed full-blown vulvodynia. There 

was no generalized alteration in temperature sensation. There was also no difference between 

patients’ and controls’ thresholds for heat and cold sensation, nor for heat and cold pain 

thresholds at a distant site, along the C5 dermatome of the arm. Thus, the abnormalities were 

localized to the pelvic and urogenital area and were not a generalized alteration in sensation.

She proposed a similar concept for visceral pain as currently used for neuropathic pain, which 

was that there was a spectrum of different insults that could lead to chronic visceral pain. 

Different pathogenetic mechanisms may require different pain treatment strategies. It was also 

possible that patients with visceral pain may have multiple co-existing pathogenetic mechanisms. 

Therefore, one would need one or several modalities to really reduce the pain in these patients to 

a significant extent.

Discussion

One participant commented that ongoing pain in one viscera could turn on central sensitization, 

to sensitize a second viscera. This was secondary hyperalgesia. Dr. Wesselmann indicated that 

the insertion of the probe was painful.

Dr. Marshall Devor, Harvard University

Dr. Devor was asked to address two different subjects: neuropathy and heritability. Normal pain 

presumed that the pain detection system was intact, and that it was detecting a true injury, 

whereas, in neuropathy, the pain-detection system itself was damaged. If a nerve was injured, 
Vulvodynia: Toward Understanding a Pain Syndrome

23

there ought to be less sensation. Paradoxically, neuropathy was often associated with positive 

symptoms, including spontaneous burning pain, allodynia, itch, pain on movement or deep 

palpation, hyperalgesia, hyperpathia, and paroxysmal pains. These symptoms were seen 

following experimental sectioning of a peripheral nerve and occurred after amputation, as in the 

“phantom limb” phenomenon. Ongoing activity generated by nerve injury could be eliminated 

by local anesthetics. Post-exotomy, the cell bodies in the dorsal ganglia also developed a large 

amount of ongoing electrical spike activity. Following a nerve cut, the ectopic activity that 

originated in the ganglion versus from the peripheral neuroma could be as high as 75 percent and 

25 percent, respectively. 

Following injury, the cell body changed its behavior and phenotype. The sensitive sodium 

channel was up-regulated at about the same time that neuropathic pain behavior came on. 

Sodium channels, which were key molecules for electrical excitability, accumulated at the 

proximal part of the nerve injury site. To explain allodynia, Dr. Devor used the Chung model of 

surgical denervation. Normal animals hardly responded to forces up to 30 grams, while the 

operated side of the test animals quickly responded to 1-2 grams. The hypothesis thus far was 

that ectopic firing generated in the injured nerve or the dorsal ganglion entered the spinal cord 

and set up a central hyperexcitability state known as central sensitization. Thus, input in the 

remaining basically intact fibers was amplified and felt as pain. At the same time, the fast 

conducting, myelinated A beta fibers, which were low-threshold mechanoreceptors, were 

recruited such that a light touch caused a pain sensation. This was called A beta pain.

Applying an anesthetic to the surface of the dorsal root ganglion or to a peripheral neuroma did 

away with tactile allodynia for the duration of the block. Dr. Devor mentioned that Richard 

Gracely had demonstrated that injecting a small peripheral neuroma ablated pain over an entire 

extremity. Thus, in the neuropathic hypothesis of vulvodynia, damage to the pudendal nerve 

from any cause, at any site, could lead to ongoing burning pain and neurogenic inflammation. In 

this scenario, the vulvar tissue was completely normal and the problem was due to the 

neuropathy.

Ectopic firing was very sensitive to membrane-stabilizing drugs at concentrations much lower 

than needed to stop nerve conduction. Infusion of very low doses of local anesthestics, such as 

lidocaine, into the bloodstream was such an example. Almost all of the drugs used today to treat 

neuropathic pain, such as the anticonvulsant carbamazepine, were of this sort. Amitriptyline, 

which had always been considered an antidepressant or a centrally acting drug, demonstrated a 

peripheral effect, as did gabapentin. In small studies, these drugs were reported to have a 

positive effect in vulvodynia. Larger placebo-controlled trials were needed.

Although variability in pain response was traditionally thought of in terms of socialization, etc., 

recent animal work showed that more than 50 percent of this variability was accounted for by a 

heritable component. Dr. Devor’s research team was able to breed a group of rats that were 

protected from neuropathic pain, and another group that was susceptible. Crossbreeding 

revealed that pain susceptibility was caused by a single autosomal-recessive gene, while 

protection from pain was dominant. Zed Seltzer identified an important quantitative-trait loci in 

mid-chromosome 15. Animals that expressed this high-pain phenotype also had high ectopic 

excitability in their injured nerve fibers. Susceptibility to one type of neuropathic pain did not 
Vulvodynia: Toward Understanding a Pain Syndrome

24

necessarily cause susceptibility to another, thus, it may not be global. Sex differences were 

variable from strain to strain. Several genetic mutations and polymorphisms that affected pain in 

humans were described, the most exciting of which was the discovery of the CACNA1 genetic 

mutation, a major cause of familial hemiplegic migraine.

Dr. Devor ended by saying that, whether vulvodynia was a neuropathy, a normal pain, or an 

inflammatory pain remained an open question, and that it was time to ask for the facts and get 

evidence from the patient populations.

Dr. Jay Shah, NIH Clinical Center

Dr. Shah outlined the goals of his presentation as: presenting the specific diagnostic criteria for 

myofascial pain; pointing out the commonly overlooked myofascial components of pelvic pain; 

discussing the dynamic role of muscle nociceptors; and introducing a novel microanalytical 

technique for quantitative analysis of the biochemical milieu associated with muscle pain. 

Dr. Shah defined myofascial pain as referred regional pain, which may be local or distant, from a 

“trigger point” within muscle and fascia. Myofascial trigger points were two to five hard, 

extremely tender areas in palpable taut bands along a skeletal muscle that may be active or latent, 

depending on whether they were associated with reproducible pain or not. Myofascial pain was 

characterized as cramping or aching and may be accompanied by autonomic dysfunction. 

Dr. Shah explained that a nociceptor was a receptor that was preferentially sensitive to noxious 

stimuli, and whose activation may contribute to a sensation of pain. The nociceptor for skin and 

mucosa were the thin, lightly mylinated to non-myelinated, high-threshold C fibers, which could 

be sensitized to noxious stimuli. The analogous structures in muscles were the group IV fibers, 

which constituted more than 50 percent of the axons in a muscle nerve. Nociceptors not only 

encoded noxious stimuli, which could lead to pain, but they also released neuropeptides, such as 

Substance P and CGRP, which caused vasodilatation and plasma extravasation, meaning they 

were intimately involved with inflammation and healing. He pointed out that muscle pain was 

more difficult to localize because of a lower density of muscle sensory afferents compared to 

skin, and because there was a convergence of sensory input at the dorsal horn of the spinal cord 

from skin, bone, viscera, and periosteum.

He emphasized that treatment for myofascial pain required a multi-faceted approach, including: 

manual techniques, dry needling, trigger-point injections, physical modalities, and approaches to 

the psycho-emotional components of pain. He added that his preferred technique for dryneedling was to use an acupuncture needle (which has a rounded tip that pushes cells aside 

compared to a bevel-edge hypodermic that is designed to tear cells) for treating myofascial 

trigger points. After careful examination and palpation, he inserted the needle directly into the 

active trigger point of a muscle, obtaining local muscle twitch responses, and continued the 

procedure until the twitch responses diminished and the muscle softened and became less tender.

To better understand the local mechanisms of muscle pain, he described an ongoing protocol at 

the NIH clinical center using microdialysis. This technique was being used to study the chemical 

activators of muscle pain, and to measure and differentiate a variety of biochemicals among three 
Vulvodynia: Toward Understanding a Pain Syndrome

25

clinically distinct groups at a standard anatomical location in the upper trapezius muscle: normal

(without neck pain and without trigger points); latent (patients with a trigger point but no neck 

pain); active (patients with a trigger point and neck pain of less than three months’ duration). 

Substance P, CGRP, bradykinin, norepinephrine, serotonin, TNF-a, and interleukin-1 (IL-1ß) 

were significantly higher in the active group than in the other two groups. The pH was 

significantly lower in the active group than the other two groups. At five minutes, Substance P 

and CGRP differed in all three groups, with active being more than latent, which was more than 

normal. Furthermore, eliciting a local twitch response in the active group caused a significant 

drop in Substance P and CGRP, suggesting a change in the local milieu with the local twitch 

response. This technique showed promise in determining the biochemical milieu and 

mechanisms of myofascial pain and, eventually, in determining the local effects and mechanisms 

of different treatment modalities.

Dr. Richard Gracely, University of Michigan

Dr. Gracely divided his presentation into three parts: 1) a capsule history of pain research over 

the past 30 years; 2) some background information on altered central processing as it pertained to 

vulvodynia; and 3) some new data, including the results of functional magnetic resonance 

imaging (fMRI) in fibromyalgia and other chronic pain conditions.

He pointed out different significant milestones since the 1960s. The first was Melzack’s 

proposed gate theory of pain, which stated that input from small fibers produced pain and input 

from larger fibers caused inhibition at the spinal level, while messages from the brain descended 

causing attenuation of pain. The second was the presence of endongenous substances, including 

opioids, endorphis, and enkephalins, that mimicked the action of morphine. Thirdly, there was 

central sensitization from persistent peripheral stimulation, a mechanism that increased the 

magnitude of pain. He described the observations that he and Gary Bennett made showing that 

constant firing from microneuromas could cause central sensitization such that stimulation of 

large A-beta touch fibers, which would normally not provoke pain, would evoke pain. He could 

produce the same phenomenon by injecting capsaicin into the skin. Capsaicin may cause some 

nerve damage, but it also activated focal nociceptors. In his opinion, central sensitization could 

be evoked by true nociception, such as by inflammation, by neuropathy (i.e., neuromas), or by 

sympathetic nervous system sensitivity to adrenal receptors expressed in injured nerves.

Dr. Gracely described experiments on patients with vulvodynia that he did with Maria Turner. 

In a series of patients with constant vulvar pain that extended way beyond the vulvar vestibule to 

the inner thighs and perianal area, they found that local injections of minute amounts of 

1% lidocaine without epinephrine, just underneath the openings of exquisitely tender Skene’s 

and Bartholin’s glands, resulted in abolition of the pain over the injection sites, with decreased 

pain and allodynia over the rest of the vestibule and surrounding glabrous skin. He provided 

diagrams and highlighted overlapping areas of secondary hyperalgesia along the midline of the 

vulva. He ascribed this result to nociceptive, possibly inflammatory stimuli coming from the 

ostia of Bartholin’s and Skene’s glands. Dr. Gracely then theorized that the beneficial effects of 

vestibulectomy may be the result of removing the source of the generator of this dynamic input, 

and suggested that therapies should be directed at these superficial sites.
Vulvodynia: Toward Understanding a Pain Syndrome

26

Dr. Gracely devoted the last part of his talk to current studies involving a different kind of 

sensitization, such as that seen in fibromyalgia. Inducing thumbnail dysesthetic pain with a 

dolorimeter, he had been mapping sites of brain activity with fMRI. The thumbnail was not a 

tender point for fibromyalgia, nor was it a myofascial trigger point. Thumbnail pain caused a 

response in the thalamus, primary and secondary somatosensory cortex. In a study of nondepressed patients with fibromyalgia and with controls, he demonstrated that patients 

experienced intense pain with 2 kilograms of pressure, while controls barely felt any pain. He 

noted that this finding may not be a marker for fibromyalgia because patients with low-back pain 

responded similarly. Using an equal pain comparison, patients had increased activation in five of 

seven areas identified in pain processing, while controls showed activation only in one. His 

current studies on vulvodynia, using a calibrated vulvodolorimeter, suggested that a mild 

stimulus to a densely innervated area could produce a focal discharge of the spinal cord and 

mechanical allodynia.

Session V: Evolving Therapies

Dr. Anthony Visco, University of North Carolina

Dr. Visco spoke on the hormonal effects of estrogen and progesterone on muscle and collagen 

integrity. He covered the following topics: the extracellular matrix (ECM), including collagen 

elastin, proteoglycans, and glycoproteins and the substances that affect it, such as 

metalloproteinases (MMP) and their inhibitors (TIMP); muscle, including actin, myosin, and 

their regulatory proteins; and hormonal influences on ECM and muscle. He explained some of 

the current techniques, such as using high-performance liquid chromatography (HPLC) to 

determine the amount of hydroxyproline, which, in turn, was a measure of the amount of 

collagen present. He found that the greatest difficulty in evaluating the literature rested in the 

fact that biopsies were taken from different sites, and from women at different ages.

With these caveats in mind, he indicated that, as far as prolapse was concerned, weak connective 

tissue could result from either decreased collagen overall, or from decreased collagen crosslinking, which may be influenced by increased amounts of MMP activity, a phenomenon 

negatively regulated by TIMP. MMP activity appeared to be stimulated by estrogen and 

inhibited by progesterone.

He described his experiments in which he plated RNA extracts from pubococcygeus muscle cells 

that were obtained from patients with uterine prolapse and from normal controls. Using gene 

chip technology, he found that smooth muscle actin and myosin, as well as myosin light chain 

kinase were 11 to 12 times overexpressed in patients. Tenacin C, involved in adult tissue 

remodeling was also overexpressed. Myosin-binding protein, myosin skeletal muscle, and C-fos 

were markedly underexpressed. Using reverse transcription PCR (rtPCR) for confirmation, he 

found a three-fold reduction in myosin heavy polypeptide three in patients with prolapse.

On the question of estrogen and progesterone receptors, a MEDLINE/PubMed search revealed 

several studies. One found a significant increase of estrogen, progesterone, and androgen 
Vulvodynia: Toward Understanding a Pain Syndrome

27

receptors in vaginal smooth muscle. No estrogen receptors, a moderate number of progesterone, 

and just a few androgen receptors were found in the levator ani muscle.

Dr. Visco concluded that, so far, weakness of the pelvic floor might be due to decreased amounts 

of actin or myosin, and may also have to do with regulatory proteins. The effects of estrogen and 

progesterone were yet unknown, while the effects of MMP and TIMP needed more study. 

Dr. Peter Smith, University of Kansas

Dr. Smith concentrated on the effects of estrogen on the peripheral nervous system pathways, 

emphasizing those that pertained to pain. He started out by saying that a review of the literature 

revealed a somewhat common idea that there was a relationship between estrogen and sensation, 

and that a decrease in threshold occurred with increased estrogen levels, such as during the 

menstrual cycle, during pregnancy, and estrogen replacement. However, dysesthetic vulvodynia 

was more common during menopause, when estrogen levels were decreasing. 

He pointed out that there were a lot of potential estrogen responsive sites in the nervous system. 

Utilizing estrogen receptor protein as a sign of estrogen responsiveness, several studies showed 

that this was present at all levels of the nervous system, from the cerebral cortex to the dorsal 

root ganglion. There were two types of estrogen receptor proteins, ERα and ERβ, which may 

occur singly or may co-localize. These receptors were thought to possibly have antagonistic 

effects. Estrogen bound to the receptor and was internalized in the nucleus, where it affected 

transcription to change proteins levels. Estrogen modulated sensory pathways by changing the 

levels of neurotrophic proteins, especially nerve growth factor and brain-derived neurotrophic 

factor. These factors could initiate axonal sprouting, promote neuronal survival, and modulate 

the functional properties of neurons. The situation was complicated because estrogen also 

affected the expression of receptors that detected these neurotrophic proteins. 

To assess effects of estrogen on peripheral nerves of the reproductive tract, he used PGP 9.5 as a 

panneuronal marker to label all intact axons and dopamine beta hydroxylase, a sympathetic 

marker, and CGRP to identify sensory nociceptor nerves. In experiments on rat myometria, 

during diestrus, he found numerous nerve fibers, while two-and-a-half days later, during estrus, 

he found relatively few fibers. He demonstrated that estrogen caused sympathetic nerve 

terminals to degenerate transiently, while sensory nerves in the uterus were not obviously 

affected by the estrus cycle. 

In contrast, following estrogen stimulation of the mammary gland, he demonstrated a robust 

increase of sensory nerve fibers, most of which were associated with blood vessels. There was 

no significant increase in sympathetic fibers.

Dr. Smith outlined an ongoing study of the innervation of the vagina. After giving 

ovariectomized animals estrogen for seven days, he removed the vagina and quantified 

innervation density by immunofluoesence. Using the panneuronal marker PGP 9.5, the distal 

vagina showed many submucosal nerves, with an obvious decrease following estrogen therapy, 

much like the uterus. Also in common with the uterus, vaginal sympathetic innervation was 

decreased by estrogen. However, using vasoactive intestinal polypeptide as a marker for 
Vulvodynia: Toward Understanding a Pain Syndrome

28

parasympathetic nerves, these nerves also decreased in estrogen-treated rats. There was also a 

marked decrease in sensory nerves as a result of estrogen administration. Thus, estrogen 

appeared to suppress innervation density in regions of the rodent reproductive tract.

Did increased nerve fiber density contribute to pain, as was proposed by some other speakers? 

Extrapolating results from ovariectomized animals to the menopausal state, one could 

hypothesize that increased nerve density may contribute to these pain syndromes. Did estrogen 

affect innervation density by altering production of trophic factors, and what cells were 

involved? Knowledge of the cellular and molecular mechanisms by which estrogen mediated 

peripheral neuroplasticity may give rise to novel therapeutic strategies aimed at alleviating 

vulvodynial pain.

Discussion

It was mentioned that progesterone was an excellent antagonist of estrogen. One participant 

shared his observation that taking away progestational oral contraceptives from young women 

with vulvar vestibulitis and adding topical estrogen was generally helpful. Another participant 

mentioned that healthy women on oral contraceptives, without a history of dyspareunia had a 

significant decrease in pain thresholds using Von Frey hairs, with no change in thermal 

sensitivity.

Session VI: Therapeutics

Dr. Gerald Gebhart, University of Iowa 

Dr. Gebhart spoke about his group’s work on animal models to study the mechanisms by which 

nociceptor activation from the viscera could be modulated. He started out by reviewing the some 

aspects of visceral hypersensitivity (e.g., interstitial cystitis and functional gut disorders), noting 

that these were characterized by pain and discomfort in response to physiologic stimuli, in the 

absence of pathology. He illustrated how neurons in the spinal cord received convergent input 

from a variety of sources, including skin, muscle, and other viscera. Thus, he indicated that he 

would prefer to interfere with input arising from the periphery of an organ, as Dr. Gracely 

demonstrated was possible in an earlier presentation. He also reviewed the concept that 

sensitization, such as that from previous inflammation, decreased response threshold and 

increased response magnitude and spontaneous activity leading to a tonic low level of input into 

the central nervous system.

With respect to opioid modulation of visceral nociception, he focused on peripheral kappa 

receptor (κR) agonists. He explained that there are three opioid receptors, Δ, μ, and κ. Only the 

κ subtype were able to attenuate responses to distention of hollow organ and “visceral” motor 

responses to distension, when they were restricted to the periphery. These visceral κ opiod 

effects were not reliably blocked by κR agonists, nor were these effects blocked by knocking 

down the receptors with anti-sense oligo nucleotides, suggesting that κR agonists acted at a 

non-κ opioid site, a novel site, or by a different mechanism. 
Vulvodynia: Toward Understanding a Pain Syndrome

29

These κ or κ-like agonists reduced the activity of calcium channels causing a decrease in 

neurotransmitter release in the second-order neuron in the spinal cord, hence, an analgesic effect. 

These agonists also deceased sodium currents, which were important for neuron excitability. 

Using recordings from single afferent fibers in the pelvic nerve, Dr. Gebhart noted that there was 

no decrease in response magnitude to colon distension using a ΔR agonist (i.e., DPDPE) and a 

μR agonist (i.e., morphine), whereas a selective κR agonist (i.e., U5488) caused a precipitous 

dose-dependent decrease in the response of that afferent fiber. This was true using other afferent 

fibers. The potency of these κ compounds increased when the organ was inflamed, suggesting 

that, in conditions such as interstitial cystitis and vulvodynia, there may be up-regulation of some 

of these receptors, including arylacetamides, which were very effective at blocking sodium 

currents as shown by in vitro experiments using single sensory-cell recordings. Dynorphin, an 

endogenous κR agonist, did not produce this reduction, but it does not have an arylacetamide 

structure. Thus, arylacetamides were peripherally restricted κR agonists that acted at calcium 

and sodium channels. These compounds were being tested in clinical trials.

Another mediator of nociception was Substance P. With dye-labeling, colon-distension 

experiments, Dr. Gebhart showed that Substance P receptors (SPRs) or neurokinin1 (NK1) 

localized in the commissure dorsal to the central canal of the spinal cord, and that SPRs were on 

the cell surface until the colon was inflamed or distended, upon which time they internalized (a 

measure of activation). Viscera were innervated by more than one nerve. Thus, pelvic viscera 

had innervation that went to the lumbosacral and thoracolumbar spinal cord. Distension of 

normal colon showed an increase in internalization of these receptors in the sacral and thoracic, 

but not the lumbar spinal cord. However, when the colon was inflamed prior to distension, there 

was not only a much greater receptor internalization in the sacral and thoracic spinal cord, but 

lumbar 2-5 also responded, which resulted in a spread of excitability. Dr. Gebhart then looked at 

different neurokinin (NK) receptor antagonists and found that NK1 and NK2 receptor 

antagonists, singly, did not decrease response magnitude to colon distension, whereas they were 

effective when used in combination. NK1 receptor antagonist may not have worked because the 

spinal cord released not only Substance P, but also NKA and other substances, which likely have 

effects at NK2 receptors. NK3 receptor antagonists worked as a single agent. This and a 

combination of NK1 and NK2 receptor antagonists had potential utility as analgesic drugs, 

particularly with respect to visceral analgesia.

Another promising group of drugs were the N-methyl-d-aspartate (NMDA) receptor antagonists, 

which, in animal models, were the most clearly efficacious antihyperalgesic when instilled in the 

spinal cord, with rapid reversal that lasted as long as the drug was present. Its disadvantage was 

that NMDA receptors were ubiquitous in the central nervous system, such that dysphoria and 

hallucinations were common side effects. The pharmaceutical industry was looking at other sites 

of action for this group of drugs to avoid the side effects. In answer to a question from the 

audience, Dr. Gebhart suggested that pentazocine, a κ-opioid receptor agonist that has μ receptor 

antagonist properties, might be a good agent to try for visceral pain.

Dr. Don Manning, University of Virginia and Celgene Corporation

Dr. Manning explained the hurdles to the introduction of new drugs to the U.S. market, but 

added, and on a brighter note, that there were at least 70 different compounds in clinical 
Vulvodynia: Toward Understanding a Pain Syndrome

30

development for the treatment of pain. Dr. Manning traced the evolution of pain management, 

starting with anesthetics, which were able to totally wipe out all sensory input, to analgesics 

(i.e., opioids), which were more specific for pain states, to the current development of 

antihyperalgesics, where one took the patient’s pain state and brought it back to normal without 

reducing it below the baseline pain sensitivity. He emphasized the importance of recognizing the 

difference between analgesics and antihyperalgesics because the animal models, targets, 

regulatory processes, and marketing material were different for each. He felt that some questions 

needed to be asked, including: did clinicians want anti-inflammatory activity? Did clinicians 

really want no sedation? Did clinicians want continuous or intermittent use? Were clinicians 

looking for a once-a-year dosing? What if an adverse reaction developed to such a long-lasting 

drug? Were clinicians only interested in drugs with rapid onset, considering that these drugs 

would be used for chronic pain? He pointed out that none of the current guidelines for the U.S. 

Food and Drug Administration or the European equivalents adequately dealt with chronic pain, 

and certainly not with visceral hyperalgesia, such as in vulvodynia. 

He emphasized the lack of animal models available for pain research, except those for induced 

pain. Other than those presented at this workshop, there were no models for chronic visceral 

pain. Another neglected area of research, for which there were no models, was for dysesthesias, 

such as itching, and other altered sensory states, which could sometimes be much worse for the 

patient than pain. There was also a disconnect between animal models and the human condition. 

For instance, NK1 antagonists worked extremely well in animal models, but failed miserably in 

humans. It had been suggested that once the toxicology of a new drug was worked out, a limited 

two-week human trial should be undertaken. He encouraged organizations to develop wellvalidated, well worked-out epidemiologic models of chronic pain, clarifying not only the disease 

state, but also the number of patients affected (market share). The size of the market was not as 

important as it being definable.

Genomics and molecular pharmacology had identified many targets, although their clinical 

relevance was not clear. Industry utilized a reverse process, using drugs with known efficacy to 

identify molecular targets. Gamma-aminobutyric acid B (GABA-B) receptors had been fully 

identified using baclofen; the α2Δ component of the calcium channel had been identified as the 

site where gabapentin and pregabalin would bind. Work continued on the mechanism by which 

tricyclics worked on the sodium channels.

Dr. Manning spoke about membrane stabilizers. Drugs such as lidocaine, antiepileptic drugs, 

and tricyclics blocked sodium channels so that sodium entry into the cell was prevented, which 

decreased cell excitability. Similarly, blocking calcium entry into the cell prevented release of 

neurotransmitters and the development of second level sensitization within the nervous system. 

Ziconotide, a snail toxin, quieted these calcium channels. Potassium channel stimulators, such as 

tricyclics and antiepileptic drugs, which increased potassium efflux from the cell, also stabilized 

the membrane. Experimentally, combining potassium channel stimulators with new opioid 

agents greatly enhanced their activities. The ubiquity of these ion channels necessitated 

identification of the specific channels involved in pain transmission to minimize adverse effects.

There were also receptor-targeted drugs. Capsaicin was a vanilloid receptor (VR) agonist, and a 

VR antagonist had been found to be very effective in animal models. Work was in progress 
Vulvodynia: Toward Understanding a Pain Syndrome

31

toward developing agents that would work on cannabinoid receptors CB1 and/or CB2 in the 

periphery. These compounds showed effectiveness in both the nociceptive and neuropathic 

models, making the debate over whether vulvodynia was one or the other, moot. Other classes 

of drugs in development included glutamate, nicotinic, muscarinic and acetylcholine receptor 

antagonists, adenosine receptor modulators, and glycine receptor agonists.

Dr. Manning touched on inflammatory modulators such as TNFα inhibitors, NF-κB modulators, 

and regulation of gene transcription. Finally, he described proteomics, which was looking at the 

proteins produced from the genes. These proteins were orders of magnitude more broad and 

varied than the genes themselves. Thus, pharmaceutical agents could be targeted toward specific 

abnormal proteins.

In closing, Dr. Manning appealed to the group to develop better and validated ways to study and 

diagnose clinical pain syndromes, so that tens of patients could be enrolled in registration quality 

trials of new drugs.

Dr. Keith Bley, NeurogesX, Inc. 

Dr. Bley indicated that he found the current conceptual framework to be inadequate and limiting. 

As an example, the concept of “irritable nociceptor” was used in both inflammatory and 

neuropathic pain conditions. He considered vulvodynia to be a chronic inflammatory pain 

condition, not a neuropathic one. In vulvodynia, there was evidence for sensitization, as well as 

for an increase in nerve-fiber density, whereas in neuropathic pain syndromes, there was a 

decrease in nerve-fiber density. Dr. Bley said that there was evidence to show that, when 

immune cells infiltrated into tissues or were in proximity to nerve fibers, there was 

hyperactivation of the sensory nervous system. For instance, superfusion of TNFα or 

interleukin-1β over nerve trunks or cultured sensory neurons in vitro resulted in robust excitatory 

responses. Moreover, cytokines could induce the Langerhans cells to proliferate in the skin; 

Langerhans cells, in turn, could increase their production of neurotrophins like nerve-growth 

factor, which was know to excite directly sensory neurons.

The work of Dr. Bley focused on the peripheral drivers for pain and on therapies directed at these 

drivers. He cited strong evidence that there were peripheral drivers to vulvodynia. First was the 

efficacy of surgical skin removal (e.g., vestibulectomy). Interestingly, similar observations had 

been made in postherpetic neuralgia. Second was efficacy of local anesthetics for vulvodynia, 

for which anecdotal evidence had been cited and there was apparently a forthcoming publication 

on this topic. In another parallel with postherpetic neuralgia, he pointed out that topical 

anesthetic patches were thought effective against this pain syndrome.

He concentrated a large portion of his talk on capsaicin, a highly selective agonist for VR1, 

which was a ligand-gated ion channel, preferentially expressed in nociceptive sensory fibers, 

which were mostly a subpopulation of C- and some Ad-fibers. These fibers had the ability to 

integrate temperature, acidification, and endogenous agonists, such as metabolites of arachidonic 

acid. One could postulate that, in chronic pain conditions, especially inflammatory pain, VR1 

was tonically activated, resulting in excessive afferent input. VR1 antagonists were promising 

medicines, and several were in development. Dr. Bley described the conditions for which 
Vulvodynia: Toward Understanding a Pain Syndrome

32

existing topical capsaicin had been helpful, but pointed out their limitations, including irritation, 

burning, and short duration of action. In experiments with low-concentration capsaicin creams, 

after one week of application, there was decreased PGP 9.5 staining of epidermal (and possibly 

dermal) nerve fibers. In order to demonstrate that comparable efficacy could be attained quickly, 

his company conducted a Phase 1 trial using a 60-minute application of an 8% capsaicin patch; 

an equivalent degree of nerve density reduction was noted. He considered high-concentration 

capsaicin to be a promising therapy for pain conditions affecting the urogenital sinus because the 

nerve fibers there express high levels of VR1. He cited the use of 30-minute capsaicin bladder 

infusions for interstitial cystitis and overactive bladder. To decrease irritancy, lidocaine 

infusions could be given prior to capsaicin instillation. He described a Phase II clinical study in 

postherpetic neuralgia using the high concentration, 60-minute patch protocol. The skin was 

pretreated with topical anesthetic, and a rescue opioid was made available. Evaluation at two to 

four weeks showed a 33 percent pain reduction from this one application, similar to that achieved 

after weeks of high-dose gabapentin therapy. High-concentration capsaicin did not produce 

adverse effects on the skin, either in the 44 postherpetic neuralgia patients, or in animal tests. 

The presumed mechanism of action was superactivation of VR1-expressing nociceptive fibers. 

These fibers were quickly pushed to a state of depolarization block, with a robust influx of 

calcium activating all calcium-dependent enzymes, which caused the fibers to become nonfunctional. Accompanying all the positive charge entering the nerve fibers was a lot of water, 

giving rise to osmotic shock as well. Because of the lack of capsaicin effects on non-VR1-

expressing fibers, it was anticipated that this situation represented a specific antihyperalgesic that 

could abolish peripheral ectopic drivers, while preserving normal sensations. Dr. Bley 

mentioned that in the postherpetic neuralgia study, patients were pretreated with an effective 

topical anesthetic, and this alone caused a robust and rapid reduction in pain, a phenomenon also 

noted in trials involving the sole use of topical anesthetics for postherpetic neuralgia. Again, this 

finding proved that much more could be done to alleviate pain by targeting the periphery.

Another approach to inhibit drivers of peripheral ectopic activity was to go after cytokines or the 

VR1 itself with an antagonist. This approach was limited by redundancy and parallel signaling 

pathways within the nervous system.

Dr. Bley ended his talk by saying that VR1 agonist therapies, given intermittently, could 

chronically attain a level of pain relief that could then be topped off with additional local 

anesthetic therapy, or with centrally acting therapies. He added that he saw the major challenge 

as the development of a convenient, rapidly acting, and low-pungency formulation.

Dr. Sophie Bergeron, Université du Québec á Montréal

Dr. Bergeron reported the long-term follow-up results from the first prospective, randomized 

treatment outcome study comparing vestibulectomy, EMG biofeedback, and cognitive 

behavioral sex therapy with pain management. The outcome measures were pain reduction, 

improvement of sexual functioning, and psychological adjustment. She also hoped to delineate 

some predictors of outcome.

Dr. Bergeron reported that 78 women met the very specific study criteria. They were neither 

perimenopausal, nor menopausal. They had moderate to severe entry dyspareunia of at least six 
Vulvodynia: Toward Understanding a Pain Syndrome

33

months duration, without chronic pelvic pain, vulvar dysesthesia, or vaginissmus. The patients 

had a mean age of 27, with the equivalent of a university undergraduate degree, and had had 

vulvar vestibulitis for about five years. Most were cohabiting or married. They were divided 

into three treatments groups: total vestibulectomy with vaginal advancement; biofeedback, 

including muscular contraction and relaxation exercises done for 20 minutes, twice a day; and 

cognitive behavioral therapy (CBT), including half pain management and half sex therapy. Of 

these three treatments groups, only the CBT group did not experience any dropouts, despite the 

fact that the patients had significantly less trust than members of other groups that this treatment 

would help their pain. 

At the six-month follow-up, women who had vestibulectomy had significantly greater 

improvement of pain on intercourse than women in the other two groups, although all 

participants significantly improved when compared to pre-treatment levels. The vestibulectomy 

group averaged 52 percent pain reduction, while biofeedback had a 35 percent pain reduction, 

and CBT had a 38 percent reduction. Across the board, improvement was better at six months 

than at three months and was maintained at the two-and-a-half year mark. Despite this 

improvement, there was no change in frequency of sexual intercourse, nor was there an increase 

in sexual desire in any of the groups. They did not have intercourse more often than they used 

to, which was four times per month, half the frequency of unaffected women their age. Looking 

at predictors of pain, in all three groups, pretreatment pain severity predicted and explained 

9 percent to 21 percent of the variance in outcomes, depending on the treatment condition. The 

lower their trust in the treatment, the more pain they had at the end of treatment. For the 

vestibulectomy group, negative sexual attitudes explained 55 percent of the variance in the 

negative outcome of the surgery.

Dr. Bergeron considered the results of their study as supporting a biopsychosocial model of pain, 

in which sensory, cognitive, affective, and behavioral factors all played a role in the development 

and maintenance of pain. The improvement from vestibulectomy supported the theory of 

nociceptor sensitization. The findings also highlighted the importance of sex therapy to improve 

the quality of sexual functioning and to reduce the negative attitudes toward sexuality. 

She concluded by saying that multimodal treatment approaches may be necessary to achieve 

significant improvement in all aspects of the disorder, and that there was a need for randomized 

treatment outcome studies to compare multimodal and unimodal approaches.

Discussion

A participant pointed out that a difference in post-operative care might explain Dr. Bergeron’s 

finding of a 68 percent improvement in subjects undergoing vestibulectomy in contrast with an 

80 percent to 85 percent improvement reported by other investigators.
Vulvodynia: Toward Understanding a Pain Syndrome

34

Final Discussion

There was general agreement that, while much has been learned since the last workshop in 1997, 

there was much that needed to be studied in the future. The fact that the disorder was more 

prevalent than previously thought should stimulate the medical profession to educate medical 

students, residents, and practitioners about vulvodynia diagnosis and current treatments. The 

conference clearly highlighted the fact that vulvodynia was a disorder that would benefit from 

research into pain and its etiologies. Pain as a symptom occurred in many disorders and, thus, 

sufferers of vulvar pain had much to gain from studies on pain in general. It was hoped that the 

conference would stimulate basic scientists to expand the information on basic mechanisms of 

this disorder, and to encourage further studies on the etiology. Randomized trials of therapies 

based on underlying mechanisms of disease were essential, and one goal of this conference was 

to stimulate public- and private-sector physicians and scientists to carry out these needed clinical 

trials, with the ultimate goal being to eliminate the suffering of countless women and their 

families.
Vulvodynia: Toward Understanding a Pain Syndrome

35

Planning Committee

Honorary Chair:

Florence Haseltine, M.D., Ph.D.

Director, Center for Population Research 

 (CPR), NICHD 

National Institutes of Health (NIH), U.S. 

 Department of Health and Human Services 

 (DHHS)

Building 6100, Room 8B07

Bethesda, MD 20892

Tel: (301) 496-1101

Fax: (301) 496-0962

Haseltinef@mail.nih.gov

Co-Chairs:

Maria Turner, M.D.

National Cancer Institute

NIH, DHHS

Building 10, Room 12N238

Bethesda, MD 20892

Tel: (301) 496-6421

Fax: (301) 496-5370

turnerm@mail.nih.gov

Phyllis Leppert, M.D., Ph.D.

Chief, Reproductive Sciences Branch, CPR, 

 NICHD

NIH, DHHS

Building 6100, Room 8B01

Bethesda, MD 20892

Tel: (301) 496-6516

Fax: (301) 480-2389

leppertp@mail.nih.gov

Committee Members:

Jerry G. Collins, M.D.

Professor of Anesthesiology

Yale Medical School

333 Cedar Street, TMP 3

New Haven, CT 06510

Tel: (203) 785-2500

j.collins@yale.edu

Richard Gracely, M.D.

Department of Internal Medicine—

 Rheumatology

University of Michigan

101 Simpson, Box 0723

1301 Catherine Road

Ann Arbor, MI 48109-0723

Tel: (734) 615-6188

Fax: (734) 615-4873

rgracely@umich.edu

Phyllis Mate

National Vulvodynia Association

P.O. Box 4491

Silver Spring, MD 20914-4491

Tel: (410) 686-7011

Fax: (301) 299-3999

mate@nva.org

Estella Parrott, M.D., M.P.H.

Director, Reproductive Medicine 

 and Gynecology Program

Reproductive Sciences Branch, CPR, 

 NICHD

NIH, DHHS

Building 6100, Room 8B01

Bethesda, MD 20892

Tel: (301) 496-6515

Fax: (301) 480-2389

parrotte@mail.nih.gov

Ursula Wesselmann, M.D.

Associate Professor

Department of Neurology, Johns Hopkins 

 University School of Medicine

Carnegie Building 490

600 North Wolfe Street

Baltimore, MD 21287

Tel: (410) 614-8840

Fax: (410) 614-9569

pain@jhmi.edu
Vulvodynia: Toward Understanding a Pain Syndrome

36
National Institute of Child Health and Human Development (NICHD)

NIH Pub. No. 04-5462

April 2004