Do bladder neck mobility and urethral sphincter function differ during pregnancy compared with during the non-pregnant state?

The aim of the study was to assess and compare urethral sphincter (US) function and bladder neck (BN) behavior in pregnant and non-pregnant women. Urethral pressure profile parameters, intravaginal-anal pressures and BN position/mobility were compared in both pregnant and non-pregnant women. It was found that pregnancy results in a decreased maximal urethral closure pressure (MUCP)/area of continence at rest and at stress, decreased pressure-transmission ratio (PTR) values and backwards displacement of the bladder neck. No significant changes in intravaginal-anal pressures and BN mobility/downwards displacement were seen. Compared with stress continent pregnant patients, pregnant patients with stress urinary incontinence (SUI) have a lower MUCP at rest/stress and area of continence at stress, but show no difference in BN behavior. Regression analysis shows no correlation between advancing pregnancy and any of these parameters. It was concluded that pregnancy induces diminished US function and backwards displacement of the BN. Compared to continent pregnant patients, pregnant women with SUI also have a diminished US function. US parameters are not significantly modified by advancing pregnancy.