BROOKLINE, MASSACHUSETTS. The first generation of oral contraceptives (containing more than 50 micrograms of estrogen) has been associated with an increased risk of myocardial infarction (heart attack). Newer versions of oral contraceptives (birth control pills) contain much less estrogen and also contain progestin. Researchers at the Boston and Columbia Universities Schools of Public Health have just concluded an investigation to determine if the new generation of contraceptive pills is safer than the earlier ones. Their results are comforting. After studying 627 women who had suffered a heart attack and 2947 controls they conclude that the risk of heart attack is no greater among birth control pill users than among non-users except if the users smoke heavily. Women who smoke more than 25 cigarettes a day and use oral contraceptives are 30 times more likely to have a heart attack than are non-smoking women who do not use the pill. That much of the extra risk is due to the pill, and not to the smoking, is clear from the fact that heavy smokers not using the pill had an excess risk of only 12 times that of non-smoking, non-pill-using women. The researchers conclude that the current warning on oral contraceptive inserts that users should not smoke is still appropriate. NOTE: This study was partially funded by numerous pharmaceutical companies.
Rosenberg, Lynn, et al. Low-dose oral contraceptive use and the risk of myocardial infarction. Archives of Internal Medicine, Vol. 161, April 23, 2001, pp. 1065-70