For estrogen-containing patch, which factor is a contraindication due to an increased risk of thromboembolism?

• A. BMI ≥ 25
• B. BMI ≥ 30
• C. History of DVT/PE
• D. Age over 40

Answer: (B)

Estrogen-containing contraception raises the risk of blood clots (venous thromboembolism), and delivering estrogen via a transdermal patch provides steady systemic exposure. Obesity further increases that risk because excess body weight contributes to a prothrombotic state and can lead to relatively higher estrogen exposure for a given patch dose. For the transdermal patch, a BMI of 30 or greater is a defined contraindication due to this elevated thromboembolism risk.

A BMI of 25–29.9 is overweight but not by itself a stated patch-specific contraindication. A history of DVT or PE is indeed a contraindication to estrogen-containing contraception, but the question targets the obesity threshold that is specifically called out for the patch. Age over 40 raises risk as well, but is not an absolute, patch-specific contraindication by itself.