Incidence rate, age-adjusted and confounder-adjusted rate ratios for venous thromboembolism (VTE) during the puerperal period according to different risk factors.

aAdjusted incidence per 10,000 women-years at risk.bRate ratio adjusted for age, calendar-year, educational status, thrombophilia, anticoagulation treatment, medical diseases, assisted reproductive treatment, and parity.cInformation necessary for the full analysis is not available for pregnancies that ended before week 22 (7% of the risk time).