Distribution and Retention Trends of Obstetricians and Gynecologists in Japan: A Longitudinal Study

INTRODUCTION: This longitudinal study aimed to investigate the distribution and retention of obstetricians and gynecologists in Japan. METHODS: I used descriptive statistics and multivariate logistic regression to analyze data from National Census surveys administered during 1996-2016. RESULTS: Between 1996 and 2016, the number of obstetricians and gynecologists increased by 6% and urban physicians by 15%, whereas the number of rural physicians decreased by 25%. The annual retention rate, which was calculated using the square root of the biannual rates [the number of physicians still working as obstetricians and gynecologists at the time of the subsequent survey (e.g., in 1998) divided by the number of obstetricians and gynecologists in the original survey (e.g., in 1996)], was >90%. Obstetricians and gynecologists were less likely to continue to work as obstetricians and gynecologists after 30-44 years of experience (1996-2006 cohort: OR = 0.20, 95% CI = 0.17-0.25; 2006-2016 cohort: OR = 0.32, 95% CI = 0.25-0.41) and >45 years of experience (1996-2006 cohort: OR = 0.14, 95% CI = 0.11-0.17; 2006-2016 cohort: OR = 0.11, 95% CI = 0.08-0.15). The odds were lower for rural obstetricians and gynecologists (1996-2006 cohort: OR = 0.65, 95% CI = 0.51-0.82; 2006-2016 cohort: OR = 0.59, 95% CI = 0.43-0.80). As the number of female physicians increased, the number of practicing obstetricians and gynecologists also increased. In 2004, the mandatory postgraduate clinical training that was newly implemented caused a drop in the number of young doctors; however, this reversed in 2006. Rural to urban migration was steady, and the working hours were consistently long. To stabilize high retention rates, the working environments need to be improved. CONCLUSIONS: The present study clearly indicated the trend of the distribution of obstetricians and gynecologists in Japan. The result may be especially important for the health policy making in Japan.