Studies have shown that growth hormone and growth hormone releasing hormone may play a role in the progression of endometriosis by promoting endometrial cell proliferation. GnRH agonists help reduce proliferation and pain by inhibiting the effects of hormones involved in ovulation and inflammation. While the exact cause of endometriosis is unknown, retrograde menstruation and genetic factors may play a part. Common symptoms include severe pelvic pain and infertility in 30% of women with the condition.