Clinical trial NCT05800678: Cross-sectional Area of Pubovisceral Muscle in Nulliparous and Primiparous Women
Official title: Comparison of Cross-sectional Area of Pubovisceral Muscle in Nulliparous and Primiparous Women
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Pelvic Floor Disorders
Keywords: magnetic resonance imaging
levator ani muscle
denervation
Lead sponsor: Institute for the Care of Mother and Child, Prague, Czech Republic
Sponsor class: OTHER
First posted: 2023-04-05
Enrollment: 80
Sex: FEMALE
Standard ages: CHILD
ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Observational model: COHORT
Time perspective: PROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: patients of the Institute for the care of mother and child, Prague CZ

* outpatient clinic
* delivery ward and postpartum care unit

Brief summary: Pelvic-floor disorders (PFD), including pelvic organ prolapse, urinary and fecal incontinence, decrease quality of life of every fourth women. 1 The main known risk factor for PFD is vaginal delivery 2,3 causing pelvic floor muscle avulsion, ischemia or denervation.4 Ultrasound (US) and magnetic resonance imaging (MRI) are frequently used to investigate structural changes in pelvic floor muscles. The investigators aimed to focus on structural changes (atrophy) caused by muscle denervation. 5 The pubovisceral muscle (PVM) is the part of the levator ani muscle (LAM) which is most frequently injured and it is thought to be possibly denervated by overstretching 6 Recently, the most precise measurement of PVM cross-sectional area was performed by the group of DeLancey. 7 In our study, the investigators aimed to describe which are the normal values of PVM volume in nulliparous women. The investigators performed a measurement of PVM volume in women after the first vaginal delivery.

The investigators hypothesized that there will be a decrease of the cross-sectional area of the PVM developed after denervation trauma.

Detailed description: Two groups of women were recruited. First, the nulliparous group served as a control. The second group was women after their first vaginal delivery. Personal characteristics, anamnestic and delivery data were collected, and clinical examination, ultrasound (US) and magnetic resonance imaging (MRI) was performed. The number of women to reach significance in the study was 40/per group. The investigators did not expect a transfer of patients between the two groups. Volunteers were recruited from a general gynecological outpatient clinic. They were thoroughly informed and informed consent was provided.

In nulliparous women, all examinations (clinical, US, MRI) were performed only once. In women after vaginal delivery, first US was performed within 72h after childbirth, in order to detect LAM avulsion and exclude these women. In women without avulsion, 6 weeks after delivery, during a general postpartum checkup, the clinical evaluation of pelvic floor muscle contraction was performed. In those where the score is 0-3 the 3D US was performed to confirm no change of hiatal area during contraction. Those scans were recorded as investigated data. Those women underwent MRI within 4 months US images were obtained with a GE Voluson E10 system (General Electric Healthcare, Chicago, IL) by one investigator. US data acquisition was performed translabial as already described.9 Volumes were acquired at rest, during Valsalva and contraction. From acquired volume was assessed PVM avulsion, size of urogenital hiatus. Decrease of hiatal area at contraction proves muscle function. The assessment of US scans was performed off-line at axial plane using the 4D View v 2.1-5.0 software (GE Medical Systems) by two investigators blinded against all clinical data. MRI images were obtained with a 3-T scanner (AchievaTM, Philips Healthcare). MRI included coronal, axial, and sagittal proton density-weighted sequences performed at rest, Valsalva and contraction. Primary outcome evaluated by MRI will be the cross-sectional area of the PVM. The precise MRI technique was already defined by the group of DeLancey and is in detail described in recent publication.7 Evaluation was performed off-line by two investigators blinded against all clinical data using ImageJ software. Intra- and interobserver variability was calculated.

Eligibility criteria: Inclusion Criteria:

* reproductive age
* vaginal birth

Exclusion Criteria:

* history of gynecological surgery or disorder with possible impact on pelvic floor
* forceps, vaccumextraction)
* labour induction
* pregnancy-related disorders
* perineal tear grade III-IV (women with episiotomy were included)
* suspicion of LAM avulsion by ultrasound or palpation
* Oxford score 4 or 5 after delivery

Primary outcomes:
measure: cross-sectional area of pubovisceral muscle
timeFrame: in nulliparous group measurements performed imediately after MRI. In primiparous group the MRI was performed within 3-6 months after delivery
Secondary outcomes:
Other outcomes:
Locations:
city: Prague
country: Czechia
facility: Institute for mother and child care
Study officials:
affiliation: Ústav pro péči o matku a dítě, Praha, CZ
name: Lucie Hájková Hympánová, PhD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Nygaard I, Barber MD, Burgio KL, Kenton K, Meikle S, Schaffer J, Spino C, Whitehead WE, Wu J, Brody DJ; Pelvic Floor Disorders Network. Prevalence of symptomatic pelvic floor disorders in US women. JAMA. 2008 Sep 17;300(11):1311-6. doi: 10.1001/jama.300.11.1311.
citation: DeLancey JO. The hidden epidemic of pelvic floor dysfunction: achievable goals for improved prevention and treatment. Am J Obstet Gynecol. 2005 May;192(5):1488-95. doi: 10.1016/j.ajog.2005.02.028.
citation: MacArthur C, Wilson D, Herbison P, Lancashire RJ, Hagen S, Toozs-Hobson P, Dean N, Glazener C; Prolong study group. Urinary incontinence persisting after childbirth: extent, delivery history, and effects in a 12-year longitudinal cohort study. BJOG. 2016 May;123(6):1022-9. doi: 10.1111/1471-0528.13395. Epub 2015 Apr 2.
citation: Weidner AC, Jamison MG, Branham V, South MM, Borawski KM, Romero AA. Neuropathic injury to the levator ani occurs in 1 in 4 primiparous women. Am J Obstet Gynecol. 2006 Dec;195(6):1851-6. doi: 10.1016/j.ajog.2006.06.062.
citation: Carlson BM. The Denervated Muscle: 45 years later. Neurol Res. 2008 Mar;30(2):119-22. doi: 10.1179/174313208X281127.
citation: DeLancey JO, Sorensen HC, Lewicky-Gaupp C, Smith TM. Comparison of the puborectal muscle on MRI in women with POP and levator ani defects with those with normal support and no defect. Int Urogynecol J. 2012 Jan;23(1):73-7. doi: 10.1007/s00192-011-1527-8. Epub 2011 Aug 6.
citation: Masteling M, Ashton-Miller JA, DeLancey JOL. Technique development and measurement of cross-sectional area of the pubovisceral muscle on MRI scans of living women. Int Urogynecol J. 2019 Aug;30(8):1305-1312. doi: 10.1007/s00192-018-3704-5. Epub 2018 Jul 5.