Amnioreduction in the management of polyhydramnios complicating singleton pregnancies

The purpose of this study was to evaluate the contribution of amnioreduction to the management of singleton pregnancies that are complicated by symptomatic polyhydramnios.

Retrospective review of all singleton pregnancies that received at least 1 amnioreduction for polyhydramnios from 2000-2012 at a single obstetric unit that provides a statewide service. The indications, procedural techniques, and pregnancy outcomes were evaluated.

One hundred thirty-eight women with polyhydramnios (maximal vertical pocket [MVP], ≥8 cm) had 271 amnioreduction procedures during the study period. The median gestation at the first drain was 31.4 weeks (interquartile range, 28.4-34 weeks) and a median of 1 procedure (interquartile range, 1-2 procedures) was performed per pregnancy. Sixty-three women (45.6%) required >1 amnioreduction. The median volume removed per pregnancy was 2100 mL (interquartile range, 1500-4260 mL). The median duration from the first amnioreduction until delivery was 26 days (interquartile range, 15-52.5 days). There was no significant association between gestation at delivery and the volume per procedure or total volume that was removed. Earlier gestation at first drain was associated positively with earlier gestations at delivery. In 4.1% of amnioreduction procedures (11/271 procedures), there was an unplanned preterm birth within 48 hours. The median gestation at delivery was 36.4 weeks (interquartile range, 34-38 weeks). The final diagnoses were gastrointestinal malformations (21%), idiopathic polyhydramnios (20.3%), chromosomal anomaly (15.2%), syndromic condition (13.7%), and neurologic condition (8%).

Amnioreduction has a useful role in the management of polyhydramnios in singleton pregnancies. Complications are uncommon, and delivery typically occurs near term.