Should You Stop Taking Birth Control Pills if You're Over 35?

Last year, I contemplated my risk of staying on birth control pills until I reach menopause and lamented the dearth of research on the long-term use of contraceptives by women. Well, I feel a little vindicated after reading a review paper published yesterday in the Journal of the American College of Cardiology. The authors, female cardiologists from Cedars-Sinai Medical Center in Los Angeles, complain that there aren't well-designed trials looking specifically at how birth control pills and other hormonal products affect a woman's risk of developing heart disease.

While a woman's risk of having a heart attack in her 30s or 40s is extremely low, heart disease death rates have recently risen in women ages 35 to 44, and no one knows exactly why. This could be due to an increase in obesity, sedentary lifestyle, and smoking, all of which raise heart disease risk. But it could also be because more middle-aged women are using hormonal contraceptives today than ever before. The paper, study coauthor Noel Bairey Merz tells me, is a resounding call for more research.

"If these were male contraceptives, we'd know so much more already," she contends. Those are fighting words; but as director of the Women's Heart Center at Cedars-Sinai, Merz has long studied the gender disparities that exist when it comes to screening and treating women for heart disease.

Containing a combination of the female hormones estrogen and progestin (a synthetic version of progesterone), birth control pills appear to protect against uterine and ovarian cancer and strengthen bones. They may or may not raise breast cancer risk, and their effects on women's hearts and arteries still aren't completely known. The review study found that oral contraceptives may slightly affect cholesterol levels, shifting the "good" HDL cholesterol downward; they may also raise blood pressure, worsen glucose tolerance (a factor in diabetes), and increase the risk of rare blood clots.

But you may not need to worry. "For healthy, lean, nonsmoking women, oral contraceptives can safely be continued into their early 50s," says Andrew Kaunitz, associate chairman of the department of obstetrics and gynecology at the University of Florida College of MedicineJacksonville, "allowing them to maintain effective contraception and even avoid perimenopausal symptoms like hot flashes and irregular bleeding." (Though these symptoms often hit once women go off estrogen cold turkey.)

You might want to reconsider, though, if you're over 35 and already at increased risk of heart disease because of one or more of the following factors:

• Smoking: Never, ever take the pill if you smoke—especially if you're over 35. You'll up your odds of blood clots, heart attacks, and strokes, especially if you smoke more than 15 cigarettes a day. Of course, quitting cigarettes will do your heart far more good than avoiding the pill will.

• Obesity: A few extra pounds probably isn't risky, but obese women—defined as having a body mass index over 30—have nearly twice the risk of developing dangerous blood clots if they take the pill compared with women at a healthy body weight.

• High blood pressure: If you have a history of high blood pressure, even if it's well controlled, it's probably best to avoid the pill because it can have a blood-pressure-raising effect. Women under 35 whose hypertension is controlled with medication can safely try oral contraceptives if their blood pressure is monitored, says the American College of Obstetricians and Gynecologists.

• Diabetes: The jury's still out as to whether oral contraceptives adversely affect a diabetic's blood sugar levels, but to be on the safe side, ACOG recommends that women over 35 with diabetes avoid the pill.

• High cholesterol: Women whose LDL cholesterol is over 160 mg/dL should avoid using the pill. Ditto for those with a family history of premature heart disease or those with an HDL level less than 35 mg/dL or a triglyceride level greater than 250 mg/dL.

• Migraines: Here's a surprise, at least to me. ACOG recommends against using the pill if you get migraines because some studies have shown that the combination increases a woman's risk of having a stroke by two to three times. I'm going to check with my doctor on this one since I occasionally get migraines—though I used to have far more of them before I went on the pill.

If you're not a good candidate for the pill, safe alternatives include progestin-only contraception like the Depo Provera injection, the Implanon implant, or the Mirena IUD. Nonhormonal methods like the copper IUD or tubal ligation are also available. Of course, we're all still waiting for that contraceptive pill for men. Perhaps in my daughter's or granddaughter's lifetime....

Corrected on 01/15/09: An earlier version of this story misstated the name of the Mirena IUD.