There is an increased risk of developing a blood clot during pregnancy and in the first 6 weeks after the birth. The risk for this group of women is one in 500, which is up to ten times higher than for women who are the same age but not pregnant.
Although pregnancy is rarely complicated by the development of VTE, it is important to know that PE is a leading cause of maternal death after childbirth, occurring in about one in 100,000 births. Together with bleeding after birth, PE is one of the main causes of death within 24 hours of delivery.
Figure: for this pregnant woman, the highest risk of DVT and PE is just after birth. However, it can occur at any time during pregnancy, including in the first 3 months.