Is it OK to smoke if you’re on the patch?

A: It’s best for women not to smoke while using the patch or other combined hormone methods. Women who smoke and have high blood pressure and/or are over 35 should not use combined-hormone methods of contraception — the pill, the patch, or the ring. Otherwise they take very serious health risks. The older the woman is and the more she smokes, the greater the danger. In fact, women 35 and older who smoke are 10 times more likely to have a heart attack than those who don't smoke. …

If I am overweight will the patch still work?

A: Yes. The patch is up to 99.7 percent effective against pregnancy when used correctly. Research has shown that the patch is slightly less effective for women who weigh more than 198 pounds.
 
A few studies have also suggested low-dose birth control pills may be slightly less effective for heavier women. But even for heavier women, these birth control methods are still extremely effective against pregnancy.
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