Progestin-Only Pills May Be More Effective to Treat Endometriosis than OCPs, Opinion Review Suggests

Progestin-Only Pills May Be More Effective to Treat Endometriosis than OCPs, Opinion Review Suggests

Oral progestin-only pills may be more effective than combined oral estrogen-progestin contraceptive pills (OCPs) in treating the pain and lesions associated with endometriosis, according to a new opinion review.

Progestin-Only Pills May Be A Better First-Line Treatment For Endometriosis Than Combined Estrogen-Progestin Contraceptive Pills” was written by Robert Casper, MD, and appeared in the journal Fertility and Sterility

OCPs have been the first choice to treat menstrual and pelvic pain associated with endometriosis, mainly because these pills are cheap and women feel comfortable and safe using it for birth control or to stop periods if given continuously.

However, no clinical evidence shows that OCPs actually treat endometriosis, the author said. Previous studies have shown that the risk of developing endometriosis in women currently taking OCPs is lower than those who are past users of these pills.

“It may seem incongruous that there is an observed increased risk of endometriosis in past but not present users of OCPs,” Casper wrote. “However, this finding is consistent with the fact that the large majority of women currently using OCPs are taking them for contraception or for relief of [menstrual pain] and are completely satisfied. One could speculate that those women with underlying endometriosis may eventually stop the OCP because of incomplete relief of pain and then eventually have a laparoscopy for diagnosis. This explanation suggests that the increase in endometriosis in past users is an artifact of OCP ineffectiveness in treating endometriosis.”

Casper does not recommend OCPs for smokers older than 35, or for women at risk of myocardial infarction, stroke or venous thromboembolism. Also, prolonged use of OCPs may eventually thin the endometrium that does not respond to estrogen, affecting women’s fertility.

“Given these uncertainties about the appropriateness of using OCPs for managing the pelvic pain and dysmenorrhea associated with endometriosis, I believe that the time has come to replace the OCP as the first line of treatment for endometriosis with oral progestin-only medications such as norethindrone acetate (NETA) or dienogest,” Casper wrote.

Contrary to the use of OCPs to treat endometriosis, clinical data does support the use of oral progestin-only pills to treat menstrual and pelvic pain associated with endometriosis. Also, AYGESTIN (NETA) is approved by the U.S. Food and Drug Administration (FDA) and dienogest has been approved by European and Canadian regulatory agencies — as well as by similar agencies in Australia, Japan and Singapore — to treat endometriosis.

Both drugs seem to be equally effective in reducing pain and lesion size in endometriosis patients. NETA is less expensive, but dienogest has fewer side effects.

“Based on controlled trial data, it appears that women with suspected or confirmed endometriosis may do better with oral progestin-only treatment as the first-line therapy because progestins have demonstrated benefits in reducing pain and suppressing the anatomic extent of endometriotic lesions,” Casper concluded. “Oral progestins alone can be used at any age, do not increase the risk of thrombosis, and are capable of inhibiting ovulation and inducing amenorrhea with very few side effects.”

The author added that he disagrees with the guidelines for managing endometriosis issued by the American College of Obstetrics and Gynecology (ACOG), the European Society for Human Reproduction and Endocrinology (ESHRE) and the Canadian Fertility and Andrology Society (CFAS).