Data shows that contraceptive drugs increase the risk of blood clots. Proponents for hormonal birth control argue that the increased risk in young women was a small risk to start with (between 1 and 5 of every 10,000 women), and that the increase isn’t drastic (between 3 and 9 of every 10,000). Not all forms of hormonal birth control have been shown to increase the risk of blood clots—just those that contain estrogen or certain types of progestin, which happen to be among the most popular. They include the Pill, Beyaz, Yasmin, Yaz, NuvaRing, Xulane, and Nexplanon.
Some compare the risk of blood clots while on birth control to the risk of blood clots that a woman has while pregnant or postpartum. It’s noted that the natural increase in estrogen that occurs during pregnancy and the postpartum period is much greater than what one experiences on birth control, and thus the risk of blood clots is much more elevated while pregnant or postpartum (between 5 and 20 of every 10,000 pregnant women, and 40 to 65 of every 10,000 postpartum women). First, it’s odd to compare the risks of birth control to risks inherent in pregnancy, considering one is a natural physical process and the other is the side effect of a drug—a drug that can expose women to the increased risk for blood clots for as long as she uses birth control, which could be for many years in a row. Second, the estrogen contained within hormonal contraceptives is synthetic, and not the same as naturally occurring, endogenous estrogen.
A recent study by Lucine Health Sciences shows that risk factors for clots caused by hormonal contraceptives have likely been underestimated. As we’ve seen in recent years, women on birth control are most certainly at risk for blood clots. The study also reveals that medical professionals do not always screen thoroughly for factors that can cause blood clots—factors that can lead to serious risk.
By increasing the risk of blood clots, stroke, and heart attack, hormonal contraception leads to the death of 300-400 women every year. To give some perspective, meningitis killed forty-five people in 2017. Most states mandate meningitis vaccination for college and university students. Would they consider the same kind of prevention campaigns for the deadly blood clots caused by hormonal birth control?
Click a subtopic below to view scientific references for each of the following and their connections to birth control use.
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For more information on blood clots and birth control, see the articles below.