Endometriosis is a common women's healthcare condition which is defined as the growth of endometrium (lining of the uterus) at sites outside the uterus, such as the ovaries. Endometriosis is commonly found in women with painful periods, pain with sexual intercourse, pelvic pain and infertility. Hormonal treatments, including the oral contraceptive pill (OCP) and gonadotrophin releasing hormone (GnRH) analogues are used to relieve the pain symptoms associated with endometriosis. There is some evidence to suggest that such treatments may also treat the actual deposits of endometriosis. However, many of the hormonal treatments have side effects which limit their acceptability and duration of use. Surgery may also be used to remove the deposits.
This review searched for studies which compared an OCP with other treatments. One small study (57 women) was found which compared an OCP to goserelin (a GnRH analogue) in two separate treatment groups. The study showed that the two treatments relieved endometriosis-associated pain equally well. The goserelin treatment stopped women from having periods. Clearly, therefore, these women did not report having pain with their periods during treatment. Goserelin can also only be safely taken for six months.
More women in the goserelin group had side effects of hot flushes, insomnia and vaginal dryness, whereas more women in the OCP group suffered headaches and weight gain. After six months follow up there were no differences between the groups. The methodology of the study was not rated highly by the review authors.