To describe the use of hydrotherapy for pain management in labor.This was a retrospective cohort study.Hospital labor and delivery unit in the Northwestern United States, 2006 through 2013.Women in a nurse-midwifery-managed practice who were eligible to use hydrotherapy during labor.Descriptive statistics were used to report the proportion of participants who initiated and discontinued hydrotherapy and duration of hydrotherapy use. Logistic regression was used to provide adjusted odds ratios for characteristics associated with hydrotherapy use.Of the 327 participants included, 268 (82%) initiated hydrotherapy. Of those, 80 (29.9%) were removed from the water because they met medical exclusion criteria, and 24 (9%) progressed to pharmacologic pain management. The mean duration of tub use was 156.3 minutes (standard deviation = 122.7). Induction of labor was associated with declining the offer of hydrotherapy, and nulliparity was associated with medical removal from hydrotherapy.In a hospital that promoted hydrotherapy for pain management in labor, most women who were eligible initiated hydrotherapy. Hospital staff can estimate demand for hydrotherapy by being aware that hydrotherapy use is associated with nulliparity.