Long-term outcomes after previable pPROM: implications for counselling at the limit of viability

The purpose of this study is to provide institution-specific, contemporary long-term outcome data to improve counselling at the limit of viability after previable preterm prelabour rupture of membranes (pPROM). This is a retrospective cohort study (2009-2022) of infants with pPROM < 23 + 0 weeks' gestation who received active neonatal care. Primary outcome was neurodevelopmental outcome at 24-36 months' corrected age. Among 109 infants, 33 (30.3%) died before discharge. Of 76 survivors, 13 (17.1%) were lost to follow-up and outcome data were available for 63/76 (82.9% follow-up). The mean gestational age was 21.6 weeks at pPROM and 25.7 weeks at delivery. Median Bayley-III scores were 90 (IQR 73-100) for cognition, 81 (IQR 63-97) for language, and 89 (IQR 65-100) for motor function. Cerebral palsy occurred in 11.1%. Survival without moderate or severe neurodevelopmental impairment (NDI) was 72.6%; moderate NDI occurred in 11.0% and severe NDI in 16.4%. Latency duration and gestational age at rupture were not significantly associated with outcome. Severe neonatal morbidity was associated with lower survival without moderate or severe NDI (57.6% vs. 89.7%). In multivariable analysis, gestational age at birth and female sex were associated with favourable outcomes in a perinatal model; after inclusion of major neonatal morbidities, only morbidity burden remained independently associated with outcome (OR 0.39, 95% CI 0.17-0.89).

A substantial proportion of survivors after pPROM < 23 weeks achieved favourable neurodevelopment at 2-3 years. In this cohort, latency duration and gestational age at membrane rupture were not independently associated with long-term neurodevelopmental outcome. However, any influence of antenatal factors may be mediated through neonatal morbidity. These findings support individualized counselling that considers both antenatal factors and the subsequent postnatal clinical course when discussing long-term prognosis.

• Previable preterm prelabour rupture of membranes (pPROM) before 23 weeks' gestation is associated with high perinatal mortality and substantial risk of long-term neurodevelopmental impairment, but available follow-up data remain limited. • Previous studies have suggested that gestational age at membrane rupture and latency duration may influence survival, yet their association with long-term neurodevelopment among survivors remains unclear.

• In this single-centre cohort with standardized Bayley-III follow-up, 72.6% of survivors survived without moderate or severe neurodevelopmental impairment, and 83.6% survived without severe impairment at 2-3 years' corrected age. • Neonatal morbidity burden, rather than gestational age at rupture or latency duration, was more closely associated with later neurodevelopmental outcome, highlighting the importance of the postnatal clinical course for prognostication and counselling.