Contraception in women over 40

Despite declining fertility, women over age 40 still require effective contraception if they wish to avoid pregnancy. A review article outlines the risks and benefits of various contraceptive options for these women. The article, based on current evidence and published in CMAJ (Canadian Medical Association Journal), is aimed at helping physicians find the best methods for their patients.

The benefits of use outweigh the risks for most contraceptive methods used by women over 40. Even for women with risk factors for complications, methods are available that can be safely used to prevent unintended pregnancy. Several methods are considered "top-tier" by the World Health Organization, including copper IUDs, progestin implants and sterilization.

Contraceptives containing estrogen should be used with caution in women over 40 who have cardiovascular risk factors, because of the increased risk of blood clots. Although some patients are concerned about an increased risk of cancer, studies have not shown a negative link between oral contraceptive use and cancer. Use of oral contraceptives is associated with a reduced risk of endometrial and ovarian cancer.

In addition to preventing pregnancy, oral contraceptives can have some additional noncontraceptive benefits for women over age 40 years, such as alleviating heavy menstrual bleeding and diminishing hot flashes in perimenopausal women.

Condoms and diaphragms may also be effective, because failure rates are lower among older women than among younger women.

"Clinical judgment will be required to balance the risks and benefits when a woman has multiple medical conditions," writes Dr. Rebecca Allen, Warren Alpert Medical School of Brown University, Women and Infants Hospital, Providence, Rhode Island, US. "The availability of safe, effective options suggests that estrogen-containing methods should increasingly be used with caution in older women who have cardiovascular risk factors."