The new birth control pills currently on the market, containing one-fifth as much estrogen as the original pills, can safely be used by nonsmoking women, even those in their 40s, according to USC researchers who presented their findings last week at the annual meeting of the American College of Obstetricians and Gynecologists.
It was also reported that the Food and Drug Administration is expected to approve, perhaps as soon as this year, the surgical implantation under the skin of a source of birth control hormones that lasts five years. This birth control method is already used in more than 40 countries.
Because of health concerns, most American women stop using birth control pills or IUDs after their prime childbearing years, said Dr. Daniel R. Mishell, a USC gynecologist. Studies show that the pill is used by fewer than 5% of women 35 and older, and that sterilization is now most commonly used in that age group.
The original pills with strong doses of estrogen were found to increase a tendency toward blood clots. The new pills use one-fifth as much estrogen and add another hormone, progestin. Studies show that they present no increased risk of cardiovascular disease or of breast cancer. But, Mishell said, women who smoke should consider pills dangerous because nicotine and estrogen acting together worsen the risk of blood clotting.