Delivery management of a complete hydatidiform mole and co-existing viable fetus: A meta-analysis and systematic review

Objective: A twin pregnancy with a complete hydatidiform mole and co-existing viable fetus (CHMCF) is an exceedingly rare obstetric complication with few data related to perinatal treatment. This study determined the optimal timing of pregnancy termination and mode of delivery in women with CHMCF and a viable fetus.

Methods: The articles published involving CHMCF and a viable fetus from 1967 to 31 December 2020 in the PubMed and EMBASE databases were systematically reviewed. Observational cohort studies with three or more cases identified and data on delivery management were selected. The articles were analyzed independently for full text and the data were integrated. The timing of pregnancy termination and mode of delivery were calculated using Review Manager 5.4.1.

Results: There were 192 reports involving CHMCF; 209 cases had a viable fetus. According to the inclusion criteria, there were 6 case series, including 72 cases that were eligible for the analysis. The average rate of live births was 34.4%. The average duration of pregnancy was 34 weeks, ranging from 25 to 41 weeks. From 2000-2017 the live birth rate was increased year-after-year. Specifically, the live birth rate was16.7% in 2000, 33.3% in 2012, and 50% in 2017. Fifty-two cases (72.2%) had cesarean sections and 20 cases (27.8%) had vaginal deliveries. The incidence of gestational trophoblastic neoplasia was not significantly different between the two modes of delivery.

Conclusions: Ideally, a twin pregnancy with a complete hydatidiform mole co-existing with a viable fetus is managed by an obstetrician, pediatrician, and oncologist. Appropriate timing of pregnancy termination and mode of delivery are related to the pregnancy outcome.