Three‐dimensional magnetic resonance imaging assessment of levator ani in women progressing from full‐term pregnancy to 10 months postpartum

Aim To identify the anatomical morphology of levator ani (LA) in primigravidae at term pregnancy and its natural process of changing after delivery. Methods Forty‐one primigravidae (vaginal delivery: 29 women, cesarean delivery in the first stage of labor: 12 women) underwent magnetic resonance imaging (MRI) at full‐term pregnancy, 6 weeks and 10 months postpartum. Three‐dimensional (3‐D) model of LA created from MRI data using Mimics v.21.0 software and source images were assessed to determine the morphology. LA volume (LVOL) was calculated and used as indicator of muscle atrophy. Results Decrease of levator hiatus length (LH‐L) was shown in both groups since 6 weeks postpartum. In the vaginal delivery group, the differences in LVOL between time points were significant (p