Gabapentin for Pain Control After Osmotic Dilator Insertion and Prior to D&E Procedure: a Randomized Controlled Trial
Phase: PHASE4
Conditions: Abortion, Induced, Cervical Preparation, Pain
Sponsor: University of California, Davis

PROTOCOL TITLE: Gabapentin for pain control after osmotic dilator insertion and prior 
to D&E procedure: a randomized controlled trial  
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Revised: February 9, 2016 
 
1) 
Protocol Title 
Title:  Gabapentin for pain control after osmotic dilator insertion and 
prior to D&E procedure: a randomized controlled trial  
Protocol Version Date: 01/11/2018 
2) 
Objectives 
Pain management in the context of abortion is a topic that is both challenging and 
necessary to research. The Society of Family Planning (SFP 2014) lists it as a top 
research priority. Most research to date has focused on pain during the abortion 
procedure. One area that remains under investigated is women’s pain experience during 
the time osmotic dilators are in the cervix prior to the dilation and evacuation procedure. 
As a result, management of pain during this time period varies greatly and is largely 
based on anecdotal experience. Adjunctive pain management with non-narcotic 
medications such as gabapentin may have a place during this time. Gabapentin is unique 
in that it is both well tolerated with minimal contraindications and low cost with 600 mg 
doses as low as $0.24. Additionally, widespread dissemination of cell phones and text 
messaging now gives us the opportunity to communicate with women about their dilator-
related pain experience in real-time, potentially improving data quality. 
We have planned a randomized, controlled trial of repeated doses of gabapentin 
compared to placebo for pain management during the time after dilator insertion and 
prior to D&E the subsequent day. Participants will receive gabapentin 600 mg or placebo 
prior to dilator insertion. Pain scores will be measured via numeric rating scale (NRS) at 
baseline and 5 minutes after insertion while the participant is in clinic. Additional pain 
scores as well as side effect and additional analgesic use will be obtained by text message 
while the patient is a home at 2 hours, 4 hours, and 8 hours after time of dilator insertion. 
Final pain score, side effect, and analgesic use assessment will occur upon presentation to 
the pre-operative are for D&E. We hypothesize that women who receive gabapentin 
beginning at the time of dilator placement for a D&E procedure will report a smaller 
increase in pain from baseline at 8 hours after dilator placement compared to women 
receiving placebo. 
 
3) 
Background 
Osmotic dilators are an essential component of cervical preparation prior to dilation and 
evacuation (D&E) procedures. To date, research involving osmotic dilators has typically 
focused on their relationship to ease of D&E completion, either alone or in conjunction 
with pharmacologic agents such as misoprostol or mifepristone. Those studies that 
evaluate pain with dilator insertion and during the interval between insertion and the 
D&E procedure do so as a secondary outcome. [1-4] It is clear that insertion of dilators is 
more painful than using a medication and there are varied accounts of how this pain 
changes over time. [2, 3, 5] One recent study evaluating use of intrauterine lidocaine for 
pain relief during dilator placement found that visual analog scale (VAS) pain scores 
overall were actually higher during the time after dilator insertion and before D&E than 

PROTOCOL TITLE: Gabapentin for pain control after osmotic dilator insertion and prior 
to D&E procedure: a randomized controlled trial  
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Revised: February 9, 2016 
during the insertion process. [1] As there have been no studies to directly evaluate 
women’s pain during the interval between dilator insertion and D&E, this area remains an 
under evaluated aspect of women’s abortion experience. 
 
Multimodal pain management has become an area of interest across many procedural 
fields. Though no data exists regarding current pain management strategies for pain after 
dilator insertion, anecdotal experience includes recommending over-the-counter 
analgesics (e.g., acetaminophen and ibuprofen) or oral narcotics. Adjunctive analgesic 
medications have been explored within Obstetrics and Gynecology for pain management, 
primarily in the context of Cesarean delivery and abdominal hysterectomy. Gabapentin is 
one such agent which has both analgesic and antiepileptic properties and few 
contraindications. [6] Use of this agent, as compared to similar drugs such as pregabalin, 
is appealing due to its low cost. When considering commonly studied perioperative 
dosing, gabapentin can be purchased for as low as $0.24 per 600 mg dose whereas 
pregabalin is $14 per 150 mg dose. [7-12] Studies regarding preoperative use of 
gabapentin in abdominal hysterectomy have demonstrated decreased post-operative 
narcotic use, decreased nausea and vomiting, and increased patient satisfaction. [8, 13-
17] Reports regarding side effects such as sedation are varied. [8, 13-17] Data regarding 
preoperative gabapentin use and post-operative Cesarean delivery pain is more limited 
and less consistent. [7, 9, 18, 19] The heterogeneity of gabapentin dosing and overall pain 
regimen along with study design limitations make these data challenging to generalize to 
abortion procedures 
 
Ultimately, studies regarding gabapentin for pain relief in abdominal hysterectomy and 
Cesarean delivery do not serve as good proxies for using gabapentin during abortion care. 
The pain experience of laparotomy, which is confounded by various regimens of regional 
and general anesthesia, is different than that of dilator insertion and subsequent D&E. 
Recent projects by family planning fellows are evaluating the use of gabapentin for 
medical and surgical abortion in the first trimester. We propose a study to evaluate the 
effect of gabapentin on the pain experienced between dilator insertion and D&E. I believe 
this treatment will be beneficial to patients and my findings could be used to create a pain 
regimen that could encompass both cervical preparation and D&E.  Since women will be 
outside of the healthcare setting for most of their dilator experience, I plan to use short 
messaging service (SMS; text message) to allow women to communicate pain evaluation 
and analgesic use in real time. 

PROTOCOL TITLE: Gabapentin for pain control after osmotic dilator insertion and prior 
to D&E procedure: a randomized controlled trial  
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Revised: February 9, 2016 
4) 
Inclusion and Exclusion Criteria 
Patients undergoing preoperative evaluation for abortion at the UCDMC family planning 
clinic will be the population for subject recruitment.  
Women presenting for dilator insertion on the day prior to their scheduled D&E 
procedure with gestational age 15 weeks 0 days to 23 weeks 5 days at time of 
preoperative appointment will be eligible for inclusion. Eligible participants will be able 
to read and write in English. Women age 18 or greater may be included. Due to possible 
sedative effects if randomized to gabapentin, women will require a ride from the clinic to 
be included. Participants must have a text messaging enabled phone and be willing to 
send and receive text messages about their experience during the study time period.  
Exclusion criteria include current gabapentin or pregabalin use, allergy to gabapentin. 
Ibuprofen, acetaminophen or codeine, self-reported renal disease, and self-reported active 
narcotic use. Patients who are currently incarcerated will also be excluded. Adults who 
are unable to consent are not traditionally encountered due to the nature of abortion care 
(with abortion as a voluntary procedure), however they will also be excluded in the 
unlikely event this situation arises.  
Eligible women will be approached by Family Planning physicians and/or research staff 
about the study. Women will be counseled that study participation will not impact their 
clinical care. Those who are interested will be given adequate time to review the study 
consent form and to address any questions with a study investigator. Written consent will 
be obtained only after consent for clinical care is completed. There will be no advertising 
or external recruitment for this study.  
5) 
Study Timelines 
Participant’s involvement in the study will extend from recruitment during preoperative 
visit in clinic, through their overnight experience with cervical dilators in place, and end 
after their final interview in the preoperative area in the main operating room prior to 
their abortion procedure.  
Based on our current volume, we estimate that we will complete enrollment of 121 
women in 12 months (goal of February 2017 – January 2018). Between August 2015 and 
June 2016, the clinical Family Planning fellow completed 228 D&E from 15 weeks 0 
days to 23 weeks 6 days gestational age (on date of procedure) at the UC Davis Medical 
Center. Completion of the primary analysis will occur by March 2018.   
6) 
Study Endpoints 
The primary study endpoint is enrollment of 121 total participants. The study will 
be reviewed at least monthly to monitor for adverse events that would indicate 
safety issues and thus a safety-related endpoint. Adverse events will include both 

PROTOCOL TITLE: Gabapentin for pain control after osmotic dilator insertion and prior 
to D&E procedure: a randomized controlled trial  
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Revised: February 9, 2016 
medical concerns and patient privacy concerns given text message contact at 
home.  
7) 
Procedures Involved 
 
Recruitment will occur in the Division of Family Planning pre-operative clinic held once 
to twice weekly in the Lawrence J. Ellison Ambulatory Care Center of the UC Davis 
Department of Obstetrics and Gynecology. This clinic is specifically for patients seeking 
abortion procedures. Family Planning physicians and/or research assistants will obtain 
informed consent from eligible women that opt to participate (all family planning 
attendings and fellows will be trained as study personnel). An institutional HIPAA 
Authorization form will also be obtained to allow access to participant’s medical record 
for information related to the study. Study information will include demographic traits 
and information from dilator placement. 
 
The current standard of care at our institution is for women to present for pre-operative 
evaluation and osmotic dilator placement on the day prior to scheduled D&E. Cervical 
anesthesia with Xylocaine 1% 20 mL is standardly administered immediately prior to 
dilator insertion. All providers follow standard guidelines on the number of dilators to 
place based on gestational age. Xylocaine is the cervical anesthetic standardly used at our 
institution as well as in other reported pain studies. [20-23] Although bupivacaine has a 
longer duration of action than xylocaine (2-4 hours and 1-2 hours, respectively), the 
increased duration does not cover the entire osmotic dilator experience. [24] 
Additionally, bupivacaine is not commonly used in cervical anesthesia-related abortion 
literature or clinical practice, limiting generalizability. Only Dilapan-S® hygroscopic 
cervical dilators are used in our practice. Misoprostol is not used in conjunction with 
dilators. Mifepristone is only used in the context of suboptimal dilator placement or 
gestational age of 22 weeks or more. After dilator placement, women standardly receive 
prescriptions for acetaminophen 300 mg/codeine 30 mg and ibuprofen 800 mg which can 
be used as needed for pain management during the time between dilator placement and 
D&E. At UC Davis Medical Center (UCDMC), D&E procedures are completed in the 
main operating rooms on the day following dilator placement with the aid of deep 
sedation. There will be no deviation from the above standard practice for 
participants in this study.  
 
Study methodology for this randomized double-blind placebo-controlled trial will 
proceed as follows: 
 
1. Eligible women at 15 weeks 0 days – 23 weeks 5 days gestational age at time of 
preoperative appointment will be approached regarding the study prior to dilator 
placement. Consent will be obtained. 
2. Relevant baseline demographics (age, race, ethnicity, education level, gravidity, 
detailed parity, reported history of anxiety, depression, drug abuse, chronic pain, 
recent narcotic pain medication use, and reason for pregnancy termination) will be 
collected. These are standard questions asked of all patients during their preoperative 
abortion evaluation. 

PROTOCOL TITLE: Gabapentin for pain control after osmotic dilator insertion and prior 
to D&E procedure: a randomized controlled trial  
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Revised: February 9, 2016 
3. Participant will be asked to provide pain level on 11-point (0-10) NRS immediately 
before study drug ingestion as the baseline pain score. Baseline symptoms (sedation 
and dizziness) will also be recorded.  
4. Women will ingest the assigned gabapentin 600 mg or placebo 
a. Stratified block randomization will occur to achieve even distribution of 
women based on vaginal parity (no prior vaginal delivery versus one or more 
prior vaginal deliveries). This strategy will ensure similar numbers of women 
with vaginal parity between gabapentin and placebo groups as this may be an 
important factor influencing pain with dilators in general.  
b. A UC Davis Investigational Drug Services (IDS) pharmacist will use 
computer-generated randomization to place active or placebo treatment in two 
groups of sequentially numbered vials (to account for block randomization 
based on parity) 
5. The physician will proceed with dilator insertion via our existing standardized 
method (including standard cervical anesthesia with 1% xylocaine 20 mL, standard 
number of dilators based on gestational age). Number of dilators and any 
pharmacologic means of cervical preparation are already reported in a standardized 
template and will be available for chart review.  
6. Post-dilator pain will be assessed via NRS at five minutes after dilator insertion. 
Additional symptoms (sedation and dizziness) will be recorded. 
7. Women will be discharged home with: 
a. One additional study medication (Gabapentin 600 mg or placebo) to take at 
home 8 hours after the initial dose. This medication will be labeled by the IDS 
and completed by administering physician. 
b. Standard prescriptions for acetaminophen 300 mg/codeine 30 mg and 
ibuprofen 800 mg to take as needed. 
c. A reminder form that includes 24-hour research contact information, the times 
when they can expect text messages,  a reminder to take the home dose of 
their assigned study medication at 8 hours after dilator insertion (exact time 
will be written out) and a reminder to bring the empty study medication bottle 
with them when they present for their procedure the next day.  
d. Recommendation that they have a ride to and from abortion procedure the 
subsequent day.  
8. Participants will be sent a baseline text message from the study phone prior to leaving 
the clinic. Participants will be encouraged to enable privacy features on their personal 
phone. Examples of security features will be reviewed and included in the consent.  
9. Participants will be contacted via text message at 2, 4, and 8 hours after dilator 
insertion.  
a. Text messages will originate from a password protected study cell phone. 
Android application “SMS scheduler” will be used to send standardized text 
messages to the participant at pre-programed time intervals from time of 
dilator insertion.  
b. Text message content: 
i. Current NRS pain score 
ii. Inventory of analgesic use since last contact 
iii. Presence of symptoms (sedation and dizziness) 

PROTOCOL TITLE: Gabapentin for pain control after osmotic dilator insertion and prior 
to D&E procedure: a randomized controlled trial  
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Revised: February 9, 2016 
iv. Reminder to take the assigned study medication (at 8 hours only) 
10. Upon admission to the pre-operative ward prior to D&E, we will document the time 
and assess the current NRS pain score, additional analgesic use since 8 hour text 
message contact, and presence of symptoms (sedation and dizziness) 
 
Blinding 
Participants and providers will be blinded to study drug allocation as all study drug will 
be prepared by the pharmacist and placed into numbered drug bottles. 
 
Privacy protection 
Participant privacy is another ethical concern in this study. Participants may have people 
with access to their cell phones who do not know about the pregnancy or abortion. 
Compromising a woman’s privacy about this matter could put her at risk depending on 
her life situation. To prevent this, I plan to use generic language that does not identify the 
context of the woman’s care. Women will be counseled regarding their ability to rescind 
their participation at any point. Below is the verbatim content of each text message that 
will be sent to participants. These text messages will be sent in order, with a programmed 
one-minute interval between each question: 
1. “What is your current pain level on a scale of 0-10? (Zero is no pain and ten is the 
worst pain imaginable)” 
2. “How many pills of ibuprofen have you taken since the last text?” 
3. “How many pills of acetaminophen with codeine have you taken since the last 
text?” 
4. “Do you feel more dizzy than usual?” 
5. “Do you feel more tired than usual?” 
 
Participants will be told about the number, timing, and generic content of text messages. 
Women will be told that the text messages will contain questions regarding their pain, 
medication use, and other symptoms.  This generic statement adequately represents the 
specific text message content as depicted above. Participants will not receive the 
verbatim text in advance. The primary reason for measuring pain via real time text 
message in this study, as opposed to home pain diary via VAS, is the benefit of 
spontaneous response which is more likely to reflect a participant’s true state. By 
providing the verbatim questions up front, participants may consciously or unconsciously 
formulate a planned response, thereby compromising the internal validity of the data in 
this study.  
 
Study drug 
Gabapentin (Neurontin®) was initially approved by the U.S. Food and Drug 
Administration (FDA) for use as an antiepileptic. [25] The FDA expanded its use to 
include postherpetic neuralgia in 2002, as research revealed gabapentin to be an effective 
treatment for neuropathic pain. [25] Off-label use has expanded to include perioperative 
and cancer pain. [25]  
 
Gabapentin is structurally similar to the gamma-aminobutyric acid (GABA) 
neurotransmitter. [26] The mechanism of action for both antiepileptic and analgesic uses 

PROTOCOL TITLE: Gabapentin for pain control after osmotic dilator insertion and prior 
to D&E procedure: a randomized controlled trial  
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Revised: February 9, 2016 
remains unknown. [26] Initiating gabapentin treatment for long term use typically starts 
at a dose of 300 mg every eight hours. [25] Dosing for perioperative use is typically 
higher though studies are heterogeneous in both dose and frequency. [25] The 
bioavailability of gabapentin actually decreases as the dose increases. For example, a 
dose of gabapentin 600 mg has 60% bioavailability, while increasing to 900 mg decreases 
to 47%. [26] For the purposes of this study, gabapentin 600 mg will balance concerns 
about lower analgesic efficacy at 300 mg doses with increased side effects without 
improved pain management at higher doses. [25] Using gabapentin 600 mg is also 
concordant with an existing fellow study investigating gabapentin use for pain during 
first trimester aspiration abortion and will add to the early research on gabapentin in 
abortion care.  
 
Interest in gabapentin for perioperative pain management is increasing in part due to its 
favorable safety profile. There are few contraindications to gabapentin use. It is excreted 
by the kidneys unchanged from its ingested form. [26] The absence of hepatic 
metabolism enables use in patients with hepatic disease or on medications that influence 
hepatic enzymes. [26] Renal insufficiency can increase the clearance time of gabapentin 
so dosage adjustment or avoidance of gabapentin is needed depending on the severity of 
renal disease. [26] Gabapentin is well tolerated in the pediatric population as well. [26] 
Most common side effects include dizziness and somnolence with less common reporting 
coordination or balance issues, peripheral edema, or gastrointestinal symptoms. [26] 
These reports are among chronic users of gabapentin. Studies investigating perioperative 
use focus more on immediate side effects experienced by gabapentin naïve patients such 
as dizziness and somnolence. [26] 
 
Study drugs will be obtained from the UC Davis Investigational Drug Services (IDS). 
The IDS is a division of UC Davis Pharmacy Services that can procure gabapentin and 
over-encapsulate it to match an identical placebo. The IDS controls participant 
randomization, maintains randomization log, and provides additional support for study 
drug administration along with accountability and adherence with state drug dispensing 
regulations. The IDS has already reviewed this research study and has formulated a plan 
for study execution with investigators. Peter Trovitch, PharmD (Senior IDS Pharmacist) 
has shadowed the Principal Investigator in the preoperative clinic to formulate a concrete 
plan for IDS drug preparation and medication accountability.  
 
Participant Compensation: 
Participants will be compensated $30 for initial study drug ingestion and completing 
baseline data collection. They will be provided based on fully answering all five text 
messages at each scheduled encounter. Compensation will include an additional $10 for 
completion of 2 hour and 4 hour text messages, and $20 for the 8 hour contact. 
Participants will receive a final $30 for completion of the assessment when presenting for 
D&E. Compensation will occur via gift cards provided to participants when presenting 
for their procedure the subsequent day. Maximum compensation per participant will be 
$100, with partial compensation possible based on participation level. Participants will be 
provided with the compensation levels. 
 

PROTOCOL TITLE: Gabapentin for pain control after osmotic dilator insertion and prior 
to D&E procedure: a randomized controlled trial  
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Revised: February 9, 2016 
8) 
Data and/or Specimen Management and Confidentiality 
 
Sample size calculation 
For the purpose of calculating sample size, there is no existing data that truly mirrors the 
objective of this study (context of pain, use of NRS, and use of change in pain score from 
baseline). The closest approximation is the mean immediate post-dilator insertion pain 
score of 5.2 (SD 1.2) via NRS from Borgatta, et al (2012). However, when using this data 
point and a commonly cited clinically significant decrease in NRS pain score of 2 points, 
computation with SAS 9.1 (factoring in power at 80% (α=0.05), normal distribution) 
yielded a small sample size of only 12 women per group. [27-33] Based on the block 
randomization there are four groups for a total of 48 women. To account for up to 20% of 
subjects not responding to text messaging for the primary outcome the sample size 
estimate will increase to 58 total women.  To ensure we gather sufficient data to truly 
outline pain experience during the dilator-procedure interval, we will more than double 
the sample size to recruit 121 women. We will stratify these 121 women by presence or 
absence of prior vaginal parity. Ensuring similar distribution of vaginal parity between 
the gabapentin and placebo groups is important as vaginal parity may affect pain with 
osmotic dilators. 
 
Statistical Analysis 
We will use non-parametric testing to assess the primary outcome variable because we do 
not expect normal distribution of the data. Chi square analysis and fisher exact tests will 
be used to compare demographics and dichotomous variables as appropriate. I plan to 
describe the pain course for the total study cohort using means and medians as 
appropriate. 
 
Data Management 
Participants will be assigned a unique study number for use on source documents and 
participant study charts. These documents will be kept in a locked file cabinet accessible 
only to study staff. Data from participant’s study charts and text message contact will be 
entered into a secure database. No identifying information will be entered into the study 
database. Only password-protected, institutionally secured UC Davis computers will be 
used for data entry and analysis. Data will be reviewed by the principal investigator and 
research coordinator to ensure accuracy and completeness. The research database will be 
banked indefinitely for the purpose of future research questions and will contain only de-
identified information as above.   
 
A cell phone will be purchased for the purposes of this study. This phone line will be 
dedicated to the study and will be password protected. It will stay with the principal 
investigator or research assistant during the times when participant follow-up is 
occurring. Outside of this time, the secured cell phone will be kept in a locked file cabinet 
with restricted access. Since the phone will not be attended at all times, participants will 
be given the standard UC Davis contact information for all clinical and study-related 
questions at any time. Our division has a dedicated phone line for family planning 
research patients that is covered by research personnel during the day (who have close 
access to an assigned family planning physician) and forwarded to the on call family 

PROTOCOL TITLE: Gabapentin for pain control after osmotic dilator insertion and prior 
to D&E procedure: a randomized controlled trial  
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Revised: February 9, 2016 
planning attending or fellow at night. All family planning attendings and fellows will be 
trained as study personnel. The cell phone’s remote data erase function and location 
service will both be activated to protect study data in the event that the phone is lost or 
stolen. 
 
Prior to first contact, the research assistant will program the participant into the phone 
contact list with their study number and preferred phone number. The Android SMS 
Scheduler application will record all scheduled and sent text messages. The application’s 
template function will be used to ensure all outgoing text messages are uniform. 
Incoming text messages are returned to the cell phone’s default text message application. 
The study cell phone will only be connected to the password protected, secure 
institutional wireless internet connection. The study cell phone’s mobile data will be 
turned off at all times to improve security. Text message responses will be input into the 
study database on a weekly basis and the participant’s contact information and text 
messages deleted from the phone.  
 
9) 
Data Banking 
 
The entire research study database, which will contain only de-identified data, 
will be banked indefinitely for the purposes of future research analysis. 
 
10) Provisions to Monitor the Data to Ensure the Safety of Subjects 
• 
Safety data will be collected throughout the study – participants will be asked 
about potential medication side effects. 
• 
Adverse event (AE): adverse experience such as symptom, physical exam 
finding, or worsening of a preexisting condition that has a temporal 
association with research participation. Causal relationship with study 
treatment is not necessary to designate an AE. 
• 
Given the contact of participants via text message in this study, significant 
breech in participant privacy will also be classified as an adverse experience. 
At enrollment, participants will be counseled to ensure they are making a fully 
informed decision to participate knowing that there will be text message 
contact with them. They will be counseled regarding ways to withdrawal if 
safety becomes a concern. If this occurs, study staff will list safety-related 
withdrawal as an AE and review as below.  
• 
Serious adverse event (SAE): adverse event that requires hospitalization, 
causes significant disability, is life threatening or results in death.  
• 
AEs will be logged and reviewed by an investigator for study drug 
relationship 
• 
Any SAE will be reported to the principal investigator once identified. The 
participant will be managed medically as indicated. All source data will be 

PROTOCOL TITLE: Gabapentin for pain control after osmotic dilator insertion and prior 
to D&E procedure: a randomized controlled trial  
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Revised: February 9, 2016 
reviewed. Physician investigators will assess for causality or relatedness of the 
adverse experience to the study.  
• 
In accordance with UC Davis institutional review board (IRB) reporting 
policy, AEs will be reported at annual IRB renewal submission. SAEs that are 
unanticipated and thought to be related to the study (thereby placing research 
subjects at higher risk of harm than originally thought) will be reported to the 
IRB by the principal investigator within five days of becoming aware of the 
event.  
• 
The study will be reviewed semimonthly at the Family Planning division 
research meeting, which includes all research staff. Any concerns regarding 
individual or trends in AEs will prompt further review of the study and 
consideration of study termination.  
• 
Study allocation will remain concealed except in a scenario in which revealing 
allocation is clinically important for the participant’s management 
11) Withdrawal of Subjects 
Based on the safety of existing research on both gabapentin for peri-procedure pain 
and an existing abortion-related study using text messaging of subjects, we do not 
anticipate frequent circumstances for participant withdrawal. There are both 
investigator and participant-initiated modes for subject withdrawal. Participants will 
be withdrawn from the study pending investigator review of AE that warrants 
removal or any SAE (see Section 10). Participants will be counseled at enrollment 
about how to withdrawal themselves from the study for any reason. If a participant 
is withdrawn from the study, no further data will be collected. We will inquire 
about the reason for withdrawal so we can monitor for AE/SAE.     
 
12) Risks to Subjects 
There are two primary categories of risk in this study: 
1. Study medication risk (Gabapentin): 
As noted in Section 7, Gabapentin is a safe, well tolerated medication that is an 
established agent of interest for peri-procedure analgesia. Contraindications and 
medication interactions are few. This study will be monitoring for the more common 
side effects that can happen (though not frequently in prior studies), including 
increased self-reported sedation and dizziness from baseline.[25]  
The FDA label for gabapentin lists adverse events reported by studies investigating 
the drug for management of either epilepsy or postherpetic neuralgia. Both FDA 
approved indications for gabapentin use a wide range of drug dosing and a 
significantly longer duration compared to this study. Studies investigating 
gabapentin for peri-procedure analgesia are powered to detect their primary outcome 
of pain reduction. Those studies reporting side effects ask about sedation and 
dizziness most commonly. [34] Gynecologic studies, typically in the context of 
abdominal hysterectomy, report no statistically significant increase in sedation or 
dizziness compared to placebo. [13-14] Both studies started with initial doses of 
gabapentin 1200 mg, which is twice the dosing of this study.[13-14] Dierking et al 
continued gabapentin dosing for a total of 3000 mg over 24 hours (year). While 

PROTOCOL TITLE: Gabapentin for pain control after osmotic dilator insertion and prior 
to D&E procedure: a randomized controlled trial  
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Revised: February 9, 2016 
participants may be able to understand the FDA risk stratification, delineating 
frequent, infrequent, and rare adverse events, the risks in the label do not accurately 
simulate the clinical context of this study.   
To minimize risks, the dose of Gabapentin used in this study is comparable to that of 
prior peri-procedure studies and the same as an ongoing randomized controlled trial 
through the family planning division at Emory University that is investigating 
Gabapentin 600 mg versus placebo for pain control during first trimester aspiration 
abortion. [25] Out of caution, participants will be required to have a ride home from 
the clinic as criteria for study eligibility so they aren’t driving after study medication 
dosing. Frequency of reported side effects will be closely monitored, as well as any 
AE or SAEs, per Section 11.   
 
2. Privacy risk: 
As noted in Section 7, participant privacy is a consideration as participants will be 
contacted while outside the healthcare setting and other individuals may have access 
to their cell phone. To protect participants’ privacy, only the above text content will 
be sent, which is generic in nature and does not identify pregnancy or abortion. 
Participants will be given a form listing the times when the text messages will be 
sent to them so they can keep the phone with them. Participants will be advised to 
also password protect their own phone and change settings so text message content 
is not displayed on their phone without unlocking it. Participants will also be given 
the 24-hour contact information for family planning research coordinators/physicians 
that can remove them from the study and discontinue any future text message 
contact if they wish.  
 
The study cell phone will only be used in the small research office/preoperative 
clinic area and will be in a locked cabinet when not in the hands of research staff. As 
noted, it will not be connected to the mobile data network and will only be used over 
the secure, password protected UC Davis wireless internet. Data will be erased from 
the phone on a weekly basis after import into the secure database. The phone’s 
remote erase and location functions will be enabled for another layer of security.  
Family planning physicians at the University of Hawaii who are completing a similar 
study (randomized controlled trial of Pregabalin versus placebo for pain with 
medication abortion, communicating with participants at home via text message 
through the SMS Scheduler Android App) have provided insight into use of the text 
messaging app/privacy protection and have reported no privacy-related adverse 
events.  
 
The form given to participants that includes text message times will identify the UC 
Davis Department of Obstetrics and Gynecology, as well as Family Planning 
physicians, in the contact information for participant questions or concerns. This 
does not pose additional risk to our participants as all patients in our pre-operative 
abortion clinic are given a folder containing copies of their signed abortion 

PROTOCOL TITLE: Gabapentin for pain control after osmotic dilator insertion and prior 
to D&E procedure: a randomized controlled trial  
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Revised: February 9, 2016 
consents, post-dilator and pre/post abortion care instructions, along with abortion 
support references.  
 
13) Potential Benefits to Subjects 
There are no direct benefits to participants.  
 
14) Community-Based Participatory Research 
Not applicable 
 
15) Sharing of Results with Subjects 
Results will not be shared with participants or other providers. 
 
16) Prior Approvals 
A concept paper detailing the background, hypotheses, design and methods of this study 
has been approved by the funding organization (Society of Family Planning). A full 
proposal has been submitted and is under review. The study will not be initiated until 
funder approval of the proposal is obtained.  
 
17) Provisions to Protect the Privacy Interests of Subjects 
See section 12 for acknowledgement of privacy risk and steps undertaken to minimize 
this risk. 
 
Participants will be made to feel at ease with the research situation by study staff using 
lay language to describe the study and to reinforce the fact that patient’s care will not be 
influenced by participation in or declination of the study. The baseline history questions, 
such as reason for abortion, substance abuse, mental health, and medical/obstetric history 
are asked of all of our pre-operative abortion patients. Obtaining answers to these 
questions ensures that we not only provide medically safe abortion procedures but that 
we can provide additional support (such as counseling resources, social work referrals) to 
patients that endorse active issues. We ask all patients about the reason for their abortion 
so we can ensure they are making an autonomous decision to terminate the pregnancy 
and are not being coerced. Additionally, we can provide support as above depending on 
the situation around the abortion (such as fetal anomaly, etcetera). As family planning 
specialists, our physicians are well trained to provide sensitive care to women seeking 
abortion every day and are thus adept to asking these standard history questions.  
 
The research staff will have access to the participant’s medical records for study purposes 
only. Participants will be notified of this and research staff will review and sign an 
institutional HIPAA release to grant this access.  
 
18) Compensation for Research-Related Injury 
The University of California, Davis Health System will provide care needed to treat 
injuries directly resulting from taking part in this research.  Insurance or third party 
payers may be billed, if appropriate, for the costs of the care subjects received.  Subjects 

PROTOCOL TITLE: Gabapentin for pain control after osmotic dilator insertion and prior 
to D&E procedure: a randomized controlled trial  
Page 13 of 15 
 
Revised: February 9, 2016 
may be responsible for some of the costs.  The University of California, Davis does not 
plan to compensate subjects for injuries. 
 
19) Economic Burden to Subjects 
 
The only potential economic cost to participants would occur if their cell phone plan 
required additional payment for text messaging responses. The compensation structure 
for the study should cover these costs if they do occur.  
 
20) Drugs or Devices 
 
The UC Davis Investigational Drug Service has been notified regarding this research 
study. Meetings between the principal investigator and IDS staff have occurred to 
formulate a plan for study drug formulation (over-encapsulated Gabapentin 600 mg with 
an identical placebo) along with drug storage, labeling, randomization, and overall 
administration oversight. Regular drug reconciliation checks will occur by the study team.  As 
noted, Peter Trovitch, PharmD (Senior IDS Pharmacist) has shadowed the Principal 
Investigator in the preoperative clinic to ensure the plan formulated can be reasonably 
executed based on clinic work flow. Study drugs will be administered only by family 
planning physicians (all family planning attendings and fellows will be trained on the 
study) in accordance with IDS instructions. The study drug will only be administered to 
enrolled study participants. Participants will administer the second dose of study drug at 
home and will have clear instructions on both the drug label (through IDS) and research 
participant form.  
 
☒ I confirm that all investigational drugs will be received by the Investigational 
Drug Service (IDS).  The IDS will store, handle, and administer those drugs so 
that they will be used only on subjects and be used only by authorized 
investigators. 
 
☒ I confirm that all investigational devices will be labelled in accordance with 
FDA regulations and stored and dispensed in such a manner that they will be 
used only on subjects and be used only by authorized investigators. 
 
 

PROTOCOL TITLE: Gabapentin for pain control after osmotic dilator insertion and prior 
to D&E procedure: a randomized controlled trial  
Page 14 of 15 
 
Revised: February 9, 2016 
 
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