Outcome in fetal lower urinary tract obstruction: a prospective registry study

Abstract

Objective: To describe influences on decision-making and prognostic variables in the prenatal management of fetal lower urinary tract obstruction (LUTO).

Methods: This was a prospective registry study of pregnant women with a male fetus with LUTO from centers within the British Isles and The Netherlands. Women and/or their clinicians were given the treatment option of either conservative management or vesicoamniotic shunting (VAS). Baseline characteristics of women in the registry, reasons for entry to the registry and pregnancy outcomes were assessed. The main study outcomes were survival to 28 days after delivery, further survival to 2 years and renal function. Logistic regression analysis was used to examine prognostic variables that affected outcome. Results were compared with those of women in a randomized controlled trial (RCT) who were allocated randomly to a treatment option.

Results: Forty-five women were registered, of whom 78% (35/45) underwent conservative management. Twenty-seven women entered the registry owing to their clinician's preference for management and 18 because of their own preference. Compared to the conservative-management group of the RCT, a higher proportion of women in the registry opting for conservative management had a normal amniotic fluid volume at diagnosis (P = 0.05) and a diagnosis of LUTO ≥ 24 weeks' gestation (P = 0.003). On multivariable logistic regression analysis, these variables showed a significant association with perinatal survival (P < 0.001). Survival to 28 days after delivery was higher in the conservative-management group, at 69% (24/35), compared to 40% (4/10) in the VAS group (P = 0.02) but this difference had limited statistical significance owing to small study size (relative risk, 0.58 (95% CI, 0.26-1.29); P = 0.14).

Conclusion: In our prospective registry, the majority of fetuses with LUTO received conservative management, which was associated with better short- and long-term outcomes. A significant proportion of these pregnancies had normal amniotic fluid volume and a gestational age at diagnosis of ≥ 24 weeks, characteristics shown to be associated with improved survival.

Keywords: congenital; perinatal mortality; prospective; renal function; urinary tract obstruction.