For women who are having their first birth and whose labor is progressing more slowly than expected, immersion in water may reduce the need for standard methods of augmentation, according to results of a study conducted in a British hospital.1 A group of women who labored in water were significantly less likely to require obstetric intervention than were a comparable group whose labor was managed with standard augmentation; those in the immersion group also reported less pain and greater satisfaction with some aspects of the approach.
The study, conducted in 1999-2000, included 99 nulliparous women with a diagnosis of dystocia (i.e., cervical dilation during active, spontaneous labor was occurring at a rate of less than 1 cm per hour). All participants were at low risk of complications and had received information about the study during pregnancy. They were randomly assigned to receive standard care for dystocia (amniotomy and intravenous oxytocin as needed) or to labor in an acrylic pool filled with tap water. Care for both groups of women was managed by midwives, who administered analgesia and monitored the progress of labor. If labor was not progressing satisfactorily, the midwives administered additional oxytocin to women in the augmentation group and advised women in the immersion group to consider augmentation.
Half of women in each group were married, and the women's average age was about 25-26 years. The two groups were similar with respect to mean gestational age at the start of labor and mean cervical dilation both at the beginning of labor and when dystocia was diagnosed. On average, the birth weights of their infants also were about the same.
Forty-seven percent of women who labored in water and 66% of those receiving standard augmentation required epidural analgesia at some point; the difference, assessed through chi-square testing, was not statistically significant. Likewise, the rate of operative delivery did not differ between groups (49-50%). However, the proportion who had labor augmented by amniotomy, oxytocin or both was significantly lower in the immersion group than in the augmentation group—71% vs. 96%. (For two women assigned to the augmentation group, labor progressed before augmentation began.) And the proportion who had any of these interventions was significantly lower among women who labored in water (80%) than among those who received standard augmentation (98%).
In postpartum interviews, women who had labored in water rated their pain 30 minutes after the start of the intervention significantly lower level than those in the augmentation group did. Furthermore, women in the immersion group reported a reduction in pain over the following half hour, while those in the augmentation group said that their pain had increased. Overall, about nine in 10 women in each group were satisfied with the labor management approach, but higher proportions in the immersion group than in the augmentation group were satisfied with the freedom of movement (91% vs. 63%) and privacy (96% vs. 81%) it afforded.
Finally, indicators of maternal and infant well-being showed little difference by approach to management of labor. Rates of both maternal and infant infections were similar in the two groups, as were infants' Apgar scores and blood gas levels. Twelve percent of infants born to mothers in the immersion group, but none of the others, were admitted to the neonatal unit within 10 days; most were released within 48 hours and had no subsequent problems.
1. Cluett ER et al., Randomised controlled trial of labouring in water compared with standard augmentation for management of dystocia in first stage of labour, British Medical Journal, 2004, 328(7435):314-319.