Physician Work Patterns in Pregnancy, Parental Leave, and Return to the Workforce.

Importance: Pregnancy and parental leave remain poorly supported in medical culture, yet little is known about how physicians adjust their workloads around childbirth. Objective: To examine work patterns of physicians before, during, and after pregnancy across specialties. Design, Setting, and Participants: This population-based retrospective cohort study included physicians registered with the College of Physicians and Surgeons of Ontario between April 1, 2002, and November 18, 2018, and had been practicing for at least 2 years prior to conception in Ontario, Canada. Physicians were followed up to November 26, 2023. Data were analyzed between January 2022 and December 2025. Exposure: Childbirth. Main Outcomes and Measures: Physician billing claims were used to identify the amount, cessation, and resumption of work activity around delivery. The rate of days worked per 100 person-days and rate of nights worked per 100 person-days according to physician specialty group prior to and during pregnancy were calculated. A negative binomial regression model was used to estimate the rate ratio of work activity in each trimester of pregnancy. The cumulative probability of return to the workforce according to specialty group was evaluated. Results: In this study, 5948 deliveries were evaluated among 3932 practicing physicians, median (IQR) age 35 (33-37) years at delivery, of which 2378 (40%) were first deliveries. Compared with prepregnancy, overall workload increased in pregnancy (RR, 1.06; 95% CI, 1.06-1.07). Workload increased in the first trimester (RR, 1.12; 95% CI, 1.11-1.12) and second trimester (RR, 1.12; 95% CI, 1.11-1.13) and then decreased in the third trimester (RR, 0.95; 95% CI, 0.94-0.97). Overnight work was reduced during pregnancy compared with prepregnancy (RR, 0.92; 95% CI, 0.89-0.95), although it increased in the first trimester (RR, 1.09; 95% CI, 1.06-1.12) and second trimester (RR, 1.05; 95% CI, 1.01-1.08), and decreased in the third trimester (RR, 0.62; 95% CI, 0.58-0.65). The cumulative probability of return to work was high for all specialties; surgeons returned the earliest (median [IQR], 133 [94-192] days). Conclusions and Relevance: In this cohort study, Ontario physicians appeared to frontload work in early pregnancy, likely to offset financial losses or group obligations. Wide variation in leave across specialties highlights inequities in how medical culture and practice structures accommodate childbearing. Supporting equitable, expected parental leave is critical to advancing gender equity in medicine.