The Food and Drug Administration on Tuesday approved the first birth control pill designed to eliminate women’s monthly period.
The new pill, called Lybrel, uses a combination of low-dose synthetic hormones that are used in other oral contraceptives already on the market. But all of the 28 pills that come in a monthly pack will contain the active ingredients, forgoing the placebo tablets that normally cause menstruation to begin.
Contraceptive makers have been introducing a variety of products designed to minimize the frequency and duration of periods.
Yaz, made by Bayer HealthCare Pharmaceuticals, and Loestrin 24 Fe, from Warner Chilcott Inc., came on the market last year with the promise of shortening periods to four days or less. Seasonale and Seasonique, sister products from Barr Pharmaceuticals Inc., limit periods to four times a year.
Lybrel, from Wyeth Pharmaceuticals, takes the trend to its logical conclusion by attempting to suppress periods altogether.
“Why have a period at all?” said Dr. Gerardo Bustillo, assistant chief of obstetrics and gynecology at Orange Coast Memorial Medical Center in Fountain Valley, Calif.
But Lybrel doesn’t quite reach that goal, based on the results of two clinical trials involving 2,400 women between the ages of 18 and 49.
According to the FDA, the women experienced unscheduled bleeding or spotting, though the incidence of such events decreased over time. In one study, only 59 percent of women who took Lybrel for one year reported no bleeding during the last month. Many women stopped taking the pill after problems with unscheduled bleeding.
In a European clinical trial, Lybrel prevented pregnancies in all 323 women who took it, according to Wyeth.
Birth control pills contain synthetic versions of estrogen and progestin that prevent ovulation. Without an egg in the uterus, a pregnancy cannot occur.
The Centers for Disease Control and Prevention estimate that 11.6 million American women use birth control pills, but it is unclear how many might prefer a product like Lybrel.
“It’s not for everybody,” said Dr. Ricardo Azziz, chair of obstetrics and gynecology at Cedars-Sinai Medical Center in Los Angeles. “Some women like to have a period every month to reassure them that they are not pregnant. Some women may feel more natural by having that period.”
Azziz estimates that 20 percent to 30 percent of women on the pill currently take it in a way that minimizes their periods. That includes a substantial number who take conventional pills, which typically come in packs of 21 active tablets and 7 placebos, and skip the sugar pills at the end of the month.
Lybrel could be an appealing option for women who take the pill to prevent nuisances like menstrual cramps and migraine headaches or to control endometriosis, Bustillo said.
“It’s not like it’s a disease to have a period, but for a lot of women it does cause problems,” he said.