Birth control pills may suppress some women’s sex drive even months after they stop taking them, says a study published today in the Journal of Sexual Medicine.
The findings could have broad implications for women’s sexual health, said Dr. Irwin Goldstein, editor-in-chief of the journal and co-author of the study.
It’s well known that birth control pills can lower libido in some women but until now, there’s not been evidence that this side effect could linger long after women stopped using the pills, he said.
“It is important for physicians prescribing oral contraceptives to point out to their patients potential sexual side effects, such as decreased desire and arousal, decreased lubrication and increased sexual pain,” said Dr. Claudia Panzer, a Denver endocrinologist and lead author of the study.
Studies also should be done to see how long these side effects last, she said.
The Panzer study has attracted interest since May, when it was presented at an endocrinology conference. Dr. Panzer said then that evidence indicated that birth control pills could cause “long-term or permanent loss of libido” in women.
Dr. John Bancroft of the Kinsey Institute for Research in Sex, Gender and Reproduction, said that, except for the Panzer study, he knew of “no other evidence that [oral contraceptives] produce irreversible effects.”
Such a claim has “potentially very serious consequences” as it might discourage women from using birth control pills, he said. “Such claims, therefore, should be based on the soundest of evidence.”
More than 100 million women worldwide use birth control pills and 80 percent of all American women born since 1945 have used them.
Birth control pills prevent contraception by altering women’s reproductive hormones. This includes increasing production of sex hormone-binding globulin (SHBG), a protein that suppresses testosterone.
Women with suppressed testosterone can suffer a loss of interest in sex and diminished sexual enjoyment.
The Panzer study involved 124 premenopausal women who sought help for sexual dysfunction at a clinic.
Researchers found that women using birth control pills had four times the amount of the SHBG protein compared with women who had never used the pills.
More important, when researchers examined women who had stopped using birth control pills for six months to a year, they found that the women’s SHBG levels were still almost twice as high as non-pill users.
Researchers need to find out if women’s SHBG levels “ever return to normal” after taking birth control pills, said Dr. Andre Guay, director of the Lahey Clinic’s Center for Sexual Function in Peabody, Mass., and study co-author.
Meanwhile, he said, when women come in with sexual problems, “we won’t dismiss that history of a birth control pill.”