Resolving polyhydramnios: clinical significance and subsequent neonatal outcome

The objective of this study was to determine the clinical significance and neonatal outcome of patients with polyhydramnios that subsequently resolved prior to delivery. A retrospective review of 275 cases of polyhydramnios, defined as an amniotic fluid index of ≥ 25.0 cm, identified 41 cases in which the amniotic fluid volume returned to normal prior to delivery. A total of 40 out of 41 patients with resolving polyhydramnios had a mild to moderate excess of amniotic fluid. There was a significant difference in the distribution of neonatal delivery weights between the study group and a matched control group. Twelve of 41 (29.3%) neonates from the study vs. none of the neonates in the control group were large for gestational age (p < 0.001). A total of 21 of 41 patients (51.2%) in the study group vs. three of 41 (7.3%) patients in the control group had at least minimal glucose intolerance (p < 0.01). We conclude that patients with resolving polyhydramnios have a significantly higher prevalence of glucose intolerance and fetal macrosomia than patients with normal pregnancies.