Related Experiment Video
Updated: Mar 25, 2026
Anogenital Distance and Perineal Measurements of the Pelvic Organ Prolapse POP Quantification System
Published on: September 20, 2018
Perineal body stretch during labor does not predict perineal laceration, postpartum incontinence, or postpartum
Kate V Meriwether1,2, Rebecca G Rogers3, Gena C Dunivan3
1Department of Obstetrics & Gynecology, University of New Mexico, 2211 Lomas NE, 4th Floor, Albuquerque, NM, 87131, USA. kvmeri01@exchange.louisville.edu.
Introduction And Hypothesis:
The perineum stretches naturally during obstetrical labor, but it is unknown whether this stretch has a negative impact on pelvic floor outcomes after a vaginal birth (VB). We aimed to evaluate whether perineal stretch was associated with postpartum pelvic floor dysfunction, and we hypothesized that greater perineal stretch would correlate with worsened outcomes.
Methods:
This was a prospective cohort study of primiparous women who had a VB. Perineal body (PB) length was measured antepartum, during labor, and 6 months postpartum. We determined the maximum PB (PBmax) measurements during the second stage of labor and PB change (ΔPB) between time points. Women completed functional questionnaires and had a Pelvic Organ Prolapse Quantification (POP-Q) system exam 6 months postpartum. We analyzed the relationship of PB measurements to perineal lacerations and postpartum outcomes, including urinary, anal, and fecal incontinence, sexual activity and function, and POP-Q measurements.
Results:
Four hundred and forty-eight women with VB and a mean age of 24 ± 5.0 years with rare (5 %) third- or fourth-degree lacerations were assessed. During the second stage of labor, 270/448 (60 %) had perineal measurements. Mean antepartum PB length was 3.7 ± 0.8 cm, with a maximum mean PB length (PBmax) during the second stage of 6.1 ± 1.5 cm, an increase of 65 %. The change in PB length (ΔPB) from antepartum to 6 months postpartum was a net decrease (-0.39 ± 1.02 cm). PB change and PBmax were not associated with perineal lacerations or outcomes postpartum (all p > 0.05).
Conclusions:
PB stretch during labor is unrelated to perineal laceration, postpartum incontinence, sexual activity, or sexual function.
