Maintenance tocolysis in twin pregnancies after preterm premature rupture of membranes and neonatal outcomes: a retrospective cohort study.

BACKGROUND: Evidence on maintenance tocolysis after preterm premature rupture of membranes (PPROM) in twin pregnancies is limited. This study evaluated the association between maintenance tocolysis and pregnancy prolongation and neonatal outcomes in this high-risk population. METHODS: This retrospective cohort study included twin pregnancies with PPROM between 24 and 34 weeks at Tongji Hospital from January 2012 to December 2022, comparing maintenance tocolysis with non-maintenance tocolysis (no tocolysis or short-term tocolysis). Primary outcomes were latency and gestational age (GA) at delivery. Secondary outcomes included perinatal mortality and morbidity. Multivariate regression was fitted, and generalized estimating equations (GEE) analyses were applied to account for within-twin clustering. RESULTS: In the main cohort, pregnancies receiving maintenance tocolysis had longer median latency (10.44 vs. 0.61 days; p < 0.001) despite earlier GA at PPROM. In the sub-cohort (delivery > 48 h), maintenance tocolysis remained associated with longer latency (adjusted β 5.21 days, 95% CI 1.64 − 8.79, p = 0.004) and higher GA at delivery (adjusted β 0.74 weeks, 95% CI 0.23 − 1.25, p = 0.004). Benefits varied by GA at rupture: early PPROM showed lower odds of patent ductus arteriosus (PDA: aOR 0.24, 95% CI 0.07 − 0.81, p = 0.021); late PPROM showed lower risk of hyperbilirubinemia (aOR 0.21, 95% CI 0.05 − 0.98, p = 0.047). In subgroup analyses, long-term tocolysis was superior to short-term therapy in extending pregnancy and reducing NICU admissions (aRR 0.91, 95% CI 0.85 − 0.99, p = 0.019) and PDA risk (aOR 0.20, 95% CI 0.06 − 0.70, p = 0.012). No significant increase in clinical chorioamnionitis (6.06% vs. 2.02%, p = 0.110) or neonatal infection was observed. However, these benefits were consistently accompanied by an elevated risk of neonatal hypoglycemia (aOR 3.75, 95% CI 1.09 − 12.95, p = 0.037) and fetal growth restriction in late PPROM (birthweight percentile: adjusted β -17.04%, 95% CI -30.27−-3.82, p = 0.012). CONCLUSIONS: In twin pregnancies with PPROM and the absence of contraindications (chorioamnionitis, placental abruption, or non‑reassuring fetal status), maintenance tocolysis effectively prolongs gestation and provides neonatal benefits that vary by rupture timing without a significant increase in infectious morbidity. These benefits must be weighed against the risks of neonatal hypoglycemia and fetal growth disturbances, underscoring a complex risk-benefit analysis for clinical decision-making.