Why are Certain Birth Control Pills Riskier for Overweight Women?

In 10 seconds? Overweight women who take contraceptive pills containing estrogens (combined oral contraceptives, COCs) face a significantly higher risk of cardiovascular events, up to 24 times more, compared to non-overweight women who do not use this method.

Wait, I know being overweight and using birth control pills are risk factors for cardiovascular diseases, so why is this noteworthy? You’re right! While it's widely recognized that both conditions increase the likelihood of thrombosis (the formation of a blood clot in the vein or artery), the above study is noteworthy because it highlights the synergistic effect of the combination of both risk factors. This means that the use of COCs among overweight/obese women amplifies the risk of thrombosis beyond what would be expected from the individual risk factors alone. In other words, the combined effect is much greater than the sum of the individual effects.