Characteristics of Women, Intrapartum Interventions, and Maternal and Neonatal Outcomes Among Users of Intrapartum Water Immersion: The UK POOL Cohort Study.

BACKGROUND

The POOL study explored intrapartum water immersion and associated maternal and neonatal outcomes at 26 UK sites 2015-2022.

METHODS

Retrospective and prospective data captured in electronic maternity and neonatal UK National Health Service (NHS) information systems. Analysis-(a) proportions of women using and factors associated with water immersion during labour or birth; (b) outcomes among "low-risk" women who used water immersion during labour or birth; (c) management and outcomes of the third stage of labour following waterbirth.

RESULTS

Among 869,744 included births, 10% (n = 87,040) used water immersion during labour or birth and 4.6% (n = 39,627) gave birth in water, with rates falling over time. Being of white or multi-ethnicity, fluent in English, non-smokers or ex-smokers, from more affluent areas, and nulliparous were associated with higher rates of water use. Overall, 39.6% of nulliparous and 9.9% of parous women at low risk at labour onset, and who used water immersion during labour, received obstetric or anesthetic care during the intrapartum period. Physiological third stage management was used following 27.1% (n = 10,737) of waterbirths and following 8.6% (n = 2260) of waterbirths the placenta was delivered into water. The rate of recorded blood loss ≥ 1000 mL was not significantly different when the placenta was delivered in water compared to placental delivery out of water.

CONCLUSION

This large UK study of water immersion during labour and birth provides important information for policymakers, maternity health professionals, and for women and families considering the option of intrapartum water immersion. Care providers need to ensure equal access to intrapartum water immersion across demographic groups and provide women with evidence-based rates of obstetric interventions that take into account their risk status and birth choices.

TRIAL REGISTRATION: ISRCTN13315580.