Non-Immune Hydrops Fetalis: Do Placentomegaly and Polyhydramnios Matter?

objectivesPolyhydramnios and placentomegaly are commonly observed in nonimmune hydrops fetalis (NIHF); however, whether their ultrasonographic identification is relevant for prognosis is controversial. We evaluated outcomes of fetal or neonatal death and preterm birth (PTB) in cases of NIHF alone and in those with polyhydramnios and/or placentomegaly (P/PM).

methodsWe conducted a retrospective cohort of singletons with NIHF evaluated between 1994 and 2013. Nonimmune hydrops fetalis was defined as 2 or more abnormal fluid collections, including ascites, pericardial effusion, pleural effusion, and skin edema. Primary outcomes were intrauterine fetal demise (IUFD) and neonatal death. Secondary outcomes were PTB (<37, < 34, and <28 weeks) and spontaneous PTB. Outcomes were compared between cases of NIHF alone and NIHF with P/PM.

resultsA total of 153 cases were included; 21% (32 of 153) had NIHF alone, and 79% (121 of 153) had NIHF with P/PM. There was no significant difference in neonatal death (38.1% versus 43.0%; P = .809) between the groups. Intrauterine fetal demise was seen more frequently in NIHF alone (34.4% versus 17.4%; P = .049). Nonimmune hydrops fetalis-with-P/PM cases were more likely to deliver before 37 weeks (80.0% versus 57.1%; P = .045) and before 34 weeks (60.0% versus 28.6%; P = .015) and to have spontaneous PTB (64.4% versus 33.3%; P = .042). Adjusted odds ratios accounting for the etiology of NIHF supported these findings, with the exception of IUFD.

conclusionsCompared to NIHF alone, pregnancies with NIHF and P/PM had a lower risk of IUFD and were at increased risk of PTB (<37 and <34 weeks) and spontaneous PTB. This information may help providers in counseling patients with NIHF and supports the need for close antenatal surveillance.