Outcomes of twin pregnancies complicated by prelabor rupture of membranes before 26 weeks of gestation: systematic review and meta-analysis

Objective: To investigate the rate of obstetric and perinatal outcomes of premature rupture of membranes (PROM) occurring before 26 weeks in twin pregnancies. Data source: Medline, Embase, Cinahl and Web of Science databases were searched electronically up to January 2024. Study eligibility criteria: The selection criteria included both prospective and retrospective studies of twin pregnancies with PROM before 26 weeks of gestation. Case reports, case series with fewer than 5 cases, review articles, letters to the editor and editorials were excluded. Studies including both singletons and twin pregnancies were also excluded. Study appraisal and synthesis method: We used meta-analyses of proportions to combine data and assess the pooled proportions. We used a random-effect model to perform the pooled data analyses. The study was registered with the PROSPERO database (CRD 42022368057). Quality assessment of the included studies was performed using the Newcastle-Ottawa Scale for cohort studies. Results: Eight studies including 227 twin pregnancies were included in the analysis. The pooled proportion of termination of pregnancy (TOP) was 4.6 % (95 % CI 1.5-13.4), while the rate of selective TOP (sTOP) was 24.5 % (95 % CI 7.1-57.7). After the exclusion of cases of TOP, the overall rate of spontaneous miscarriage or fetal demise was 20.9 % (95 % CI 11.1-35.8), whereas the live birth rate of at least one twin was 71.6 % (95 % CI 61.2-80.1) of the ongoing pregnancies. The mean gestational age at delivery was 26.5 (95 % CI 25.1-28.0) weeks and the mean latency between PROM and delivery was 5.4 weeks (95 % CI 4.8-5.9) in all cases including those with fetal deaths. Neonatal outcomes showed that the overall neonatal mortality was 26.4 % (95 % CI 16.7-39.2). When focusing only on pregnancies undergoing sTOP, the observed livebirth rate was 87.7 %. The gestational age at rupture of membranes in these cases was 16.8 (95 % CI 14.9-18.6) weeks and the latency between PROM and delivery was significantly longer (19.9 (95 % CI 18.0-21.7) weeks) than that observed in unterminated pregnancies, with a mean gestational age at delivery nearly in the range of term (36.9 weeks). Conclusions: PROM in twins before 26 weeks is associated with overall high rates of adverse obstetric and neonatal outcomes, and it represents a clinical challenge for both counseling and management. Larger prospective studies unified objective protocols in terms of antenatal surveillance and management are needed.