Preterm Prelabour Rupture Of Membranes (PPROM) before 23 weeks gestation: A prospective observational study

Abstract

Objectives Describe infant and maternal outcomes of a national cohort of women with preterm prelabour rupture of membranes (PPROM) under 23 weeks gestation. Design Prospective national population-based cohort study using the UK Obstetric Surveillance System (UKOSS). Setting All 194 obstetric units in the UK. Participants 330 women with singleton and 38 with multiple pregnancies and PPROM between 16+0 and 22+6 weeks gestation 1/9/19-28/2/21. Main outcome measures Infant outcomes: livebirth, survival to hospital discharge and severe morbidity, defined as intraventricular haemorrhage grade 3 or 4 and/or supplemental oxygen requirement at 36 weeks postmenstrual age. Maternal outcomes: surgery for placental removal; sepsis; admission to intensive treatment unit (ITU) and death. Methods All data including rates of termination of pregnancy for medical reasons (TFMR) were reported. Three rates were calculated for infant outcomes: i) all TFMR excluded; ii) assuming that all TFMR and those with missing data would have died; iii) assuming that all TFMR and those with missing data would be liveborn. Rates are presented as i (ii to iii). Results For singleton pregnancies the livebirth rate was 44% (30 to 62%), infant survival to discharge was 26% (16 to 54%) and 18% (12 to 49%) of infants survived without severe morbidity. Maternal sepsis rate was 12% for singleton and 26% for twin pregnancies. Surgery for placental removal was 20% and 14%, respectively. Five women became severely unwell with sepsis, 2 died and a further 3 required ITU care. Conclusions Although significant numbers of pregnancies with very early PPROM have favourable outcomes, morbidity and mortality rates in this cohort are high for mothers and infants. These data can be used in counselling families facing PPROM prior to 23 weeks gestation and to underpin research into the complex pathologies, including sepsis, related to this condition. Currently available guidelines should be updated accordingly.