Does levator trauma 'heal'?

To evaluate if pregnancy- and delivery-related changes to levator morphology and distensibility regress with time.

488 nulliparous pregnant women, recruited between 36 and 38 weeks' gestation, were invited for assessment at 3-6 months and again at 2-3 years postpartum. All underwent an interview and four-dimensional translabial ultrasound examination. Hiatal morphometry and bladder neck descent (BND) were determined and compared between the two postpartum visits.

367 participants returned for assessment at 4.1 (interquartile range (IQR), 3.7-5.0) months and 161 returned at 2.6 (IQR, 2.0-3.1) years, allowing a groupwise comparison. There was no significant difference in hiatal area (22 vs 22 cm(2), P = 0.95) or BND on Valsalva maneuver (26.3 vs 25.5 mm, P = 0.49). Pairwise comparison in women who had attended both postpartum appointments without second births (n = 77), separately for those who had a cesarean section (n = 24) and those who had a vaginal delivery (n = 53) originally, showed no significant changes, except a reduction in BND (31.2 vs 28.3 mm, P = 0.025) in those who had delivered vaginally. Two women out of 12 diagnosed with a levator avulsion at 3-6 months showed obvious anatomical improvement on translabial ultrasound at 2-3 years.

We found no evidence of regression or healing of pregnancy- and delivery-related changes to levator distensibility on comparing imaging data obtained at 3-6 months and 2-3 years postpartum. However, we documented anatomical improvement on translabial ultrasound at the second postpartum visit in two women diagnosed with levator avulsion at 3-6 months postpartum.