The Pill, Obesity and Blood Clots

By Dietitian, Juliette Kellow BSc RD

According to new research, obesity dramatically increases the risk of blood clots for women who take The Pill.

The European Active Surveillance (EURAS) study took place between 2000 and 2006 and included almost 59,000 women from seven European countries, including the UK. The study set out to look at heart health in women using oral contraceptives.

To help analyse the results, the researchers added all the years of the women together to make the measurements more precise.

The results showed that for every 100,000 years there were 44 cases of blood clots in women who didn’t take the Pill. This figure rose to 90 cases in women who were taking the combined Pill – around double. But when the study looked specifically at women with a BMI over 30, it found 230 cases. In other words, obese women were five times more likely to develop blood clots than those not on the Pill.

Currently, the Faculty of Family Planning warns against prescribing the combined pill to women with a BMI over 35.

However, Dr Anne Szarewski, editor-in-chief of the Journal of Family Planning and Reproductive Health Care says it’s likely that guidelines will be tightened.

WLR says:

The link between blood clots and the Pill has been known about for many years, particularly in women who are obese.

It’s thought the increased risk comes from the extra oestrogen they naturally have. However, this new study reveals that the risk is much higher than was previously thought and as a result, in the future, guidelines may be tightened.

The best suggestion is to follow the advice of your doctor and maybe use this new research as yet another incentive to shift those extra pounds.