Introduction:
Water immersion is a non-pharmacological method of pain relief during labor. Its safety for both the mother and the newborn has been established. Obstetric hemorrhage remains a major cause of maternal morbidity. This study evaluated the effect of water immersion during the first stage of labor on postpartum blood loss.

Aim:
To assess whether water immersion during the first stage of labor influences postpartum blood loss and the incidence of postpartum hemorrhage (PPH) in low-risk women.

Material and methods:
This cohort study included 240 women with singleton pregnancies at 37–41 weeks of gestation who met the eligibility criteria for water immersion. The study group consisted of 102 women who used water immersion, while 138 women served as controls. Participants self-selected into groups. Water immersion lasted 60 minutes. Blood loss was assessed visually by a midwife immediately after delivery. Hemoglobin (Hb) levels were measured on admission and 24 h postpartum. Continuous variables were compared using independent t-test, and categorical variables using χ² test or Fisher’s exact test. A p-value < 0.05 was considered statistically significant.

Results and Discussion:
No significant differences were observed between the water immersion and control groups in estimated blood loss (p = 0.09) or hemoglobin change (p = 0.81). Multivariable regression showed that water immersion was not independently associated with postpartum blood loss (p = 0.565).

Conclusions:
Water immersion during the first stage of labor was not associated with increased postpartum blood loss or a higher incidence of PPH. These findings support water immersion as a safe non-pharmacological method of labor management in low-risk women.