ABSTRACT: Background: This work sampling study examined how much time intrapartum unit nurses spend providing supportive care overall and during weekday and weekend shifts, and by patient and staff characteristics at a university hospital with 4000 births per year in Montréal, Québec. Methods: Four-hour observation periods were randomly selected to represent each shift and day of the week. Within each period, eight 15-minute observation times were randomly selected. Observers located each nurse assigned to the unit at that time and recorded her activity. Supportive activities included physical comfort, emotional support, instruction, and advocacy. Results: The percentage of time spent in supportive care was 6.1 percent (95% confidence interval 5.3%, 6.9%), based on 3367 observations. The time providing supportive care was similar for weekday and weekend shifts. Nurses with less than seven years of intrapartum experience spent 2.7 percent (0.9, 4.5) more time providing supportive care than nurses with seven years of experience or more. Supportive care was 9.2 percent (0.7, 17.7) greater for nulliparous than for parous women, and supportive care of women with epidural anesthesia was similar to those without it. Conclusions: We concluded that intrapartum unit nurses spent a small amount of time providing supportive care to women in labor. This suggests the need for perinatal caregivers and hospital administrators to reexamine how nurses spend their time, given the evidence from randomized trials showing the beneficial effects of continuous support on labor and birth outcomes.