ブラジルの独立型バースセンターにおける母体および新生児の水中出産のアウトカム：横断研究

While international studies support the safety and benefits of waterbirth, this practice is still restricted in many Brazilian services, with few opportunities for birthing people to choose this option for labour and birth.

To analyse maternal and neonatal outcomes in assisted waterbirths versus land births in a Brazilian freestanding birth centre.

We conducted a cross-sectional study using retrospective data from 2012 to 2024. Maternal and neonatal outcomes of 919 waterbirths were compared to 2,805 land births, including perineal tear and repair, postpartum haemorrhage, retained placenta, maternal and neonatal transfers, neonatal resuscitation, and Apgar scores. Odds ratios (OR), rate ratios (RR) and adjusted odds ratios (aOR) were calculated, and multivariate analysis considered previous vaginal birth as a confounder variable. The significance level was 5 %.

Waterbirth was associated with a lower likelihood of perineal tear (aOR, 0.75; 95 % CI, 0.65-0.87; P < .001), perineal repair (OR, 0.73; 95 % CI, 0.62-0.86; P < .001) and postpartum haemorrhage (aOR, 0.76; 95 % CI, 0.64-0.90; P < .002).

The findings align with international evidence that associates waterbirth with reduced perineal trauma and postpartum haemorrhage. Unlike some studies that suggest increased neonatal risks, no adverse outcomes were observed in this study.

Waterbirth was not associated with any additional risk to people with straightforward pregnancies. The results support the option of waterbirth as an informed choice for this population birthing in freestanding birth centres.