METHODS: This is a retrospective review using archived data sets of women seen in the context of two prospective perinatal imaging studies. All subjects had undergone a standardised interview, a clinical examination and 4D translabial ultrasound, 3 months and 2-5 years post-partum. Main outcome measures were pelvic organ descent and hiatal area at maximum Valsalva manoeuvre. Means at the two time points were compared using paired Student's t test. Predictors of change over time in continuous variables were explored using linear modelling methods.

RESULTS: A total of 300 women had at least two postnatal follow-ups. They were first seen on average 0.39 (SD 0.2, range 0.2-2.1) years and again 3.1 (SD 1.5, range 1.4-8) years after the index delivery, with a mean interval of 2.71 (SD 1.5, range 0.7-7.7) years, providing a total of 813 (300 × 2.71) woman-years of observation. On univariate analysis, there was a significant decrease in mobility over time of the bladder neck, bladder, and rectal ampulla (P = < 0.004) and hiatal area (P = 0.012). The degree of improvement was less marked in women with levator avulsion.