What is endometriosis?
Endometriosis is characterized as a condition in which endometrial tissue, which normally lines the uterus, develops outside of the uterine cavity in abnormal locations such as the ovaries, fallopian tubes and abdominal cavity.1 Endometriosis is a common cause of chronic pelvic pain in women and can sometimes be associated with infertility.2 It is estimated that 1 in 10 women suffer from endometriosis (with percentages even higher in women with chronic pelvic pain and infertility). On average, it takes anywhere from 3 to 11 years from the onset of pain symptoms for women to be accurately diagnosed with endometriosis.3
As pharmacists, it is important to establish our role in patient care and to be aware of this underdiagnosed condition and the role of hormonal contraception in managing symptoms and the disease. We can assist patients with endometriosis by having confidence in the medication they were prescribed and keeping in mind the individual treatment goals in each patient. While there is no definitive cure for endometriosis, there are pharmacological approaches in the management of the associated pain. While there are many different options available for women with endometriosis, this article will be focusing on the use of hormonal contraceptives in endometriosis pain management. Additionally, it is important to keep in mind that no hormones are free of side effects and severity and tolerability can vary significantly; not all types of endometrial pain respond equally to hormonal treatment.4
What is the role of hormonal contraceptives in endometriosis treatment?
Combined hormonal contraceptives (CHCs) and progesterone only pills (POPs) have been used for pain management associated with endometriosis. Hormonal contraceptives help to slow the growth of new endometrial tissue and may prevent formation of new adhesions which can help decrease the pain patients have. However, hormonal contraceptives will not eradicate any endometrial tissue that currently exists in the patient.5
There are a few differences in tolerability and the level of evidence for each treatment. For assessing the different types of contraceptive treatment for endometriosis, the European Society of Human Reproduction and Embryology (ESHRE) has created a grading scale as part of their justification for treatment:
Grade A: treatment has been backed by meta-analysis, systemic review or multiple RCTs (high quality).
Grade B: treatment has been backed by a meta-analysis, systemic review or multiple RCTs (moderate quality), single RCT, large non-randomized trial, case-control or cohort studies (high quality).
Grade C: treatment has been backed by a single RCT, large non-randomized trial, case-control or cohort studies (moderate quality).4
CHCs may considered as it can reduce endometriosis-associated dyspareunia, dysmenorrhea and non-menstrual pain.4 Oral CHCs are considered “Grade B”.4 It is important to note that endometriosis is considered to be a predominantly estrogen-dependent disease. It is possible that the estrogen component of CHCs may mask the effect of the progestin by possibly activating the disease. However, it has been argued that ethinylestradiol doses are too low to reach an activating threshold.4 According to the American College of Obstetricians and Gynecologists (ACOG) guidelines, CHCs showed significant decrease in pain in patients and if that therapy is not tolerated patient could move on to progestins. Unlike the ESHRE, they did not differentiate between types of contraceptives and their related effectiveness.5
Among the CHCs, it is important to recognize that different dosage forms have different grades of evidence of efficacy in the ESHRE guidelines. Continuous CHCs (active tablets only) were given a “Grade C”. Vaginal contraceptive rings and transdermal patches were also given a “C”.4
Progestin-only pills are considered “Grade A” by the ESHRE guidelines because they have the most evidence to date in reducing endometriosis-related pain. Additionally, while Levonorgestrel-containing IUDs are not FDA approved as treatment for endometriosis, they are given a “Grade B” as an option to reduce pain related to the disease.4 Additionally, the ACOG guidelines recognize the use of levonogersterol-containing IUDs to reduce endometriosis related pelvic pain, but emphasized that potential side effects like irregular bleeding and weight gain are common.5
Another type of progestin contraceptive that can be used for endometriosis-associated pain is Depot medroxyprogesterone (DMPA). DMPA works to prevent follicular growth preventing ovulation.6 ACOG recognizes DMPA as a suitable treatment as it has been approved by the FDA for treatment of endometriosis-associated pain.5 Furthermore, ESHRE gave DMPA a “Grade A” as an option to reduce endometriosis-related pain.4
As pharmacists, we serve a vital role in the patient care plan and can be there to help patients recognize the types of treatment options available to them. As a patient, it may be hard navigating through the different contraceptive options that they have for endometriosis pain management. Pharmacists can help patients navigate these options in order to help improve their quality of life.
- Noncontraceptive benefits of birth control pills: fact sheet. ASRM (American Society for Reproductive Medicine). Available from: https://www.reproductivefacts.org/globalassets/rf/news-and-publications/bookletsfact-sheets/english-fact-sheets-and-info-booklets/noncontraceptive_benefits_of_bcp_factsheet.pdf. Accessed January 16, 2020
- Leyland N, Casper R, Laberge P, Singh SS, SOGC. Endometriosis: diagnosis and management. J Obstet Gynaecol Can 2010;7 (Suppl 2):S1–32.
- Husby GK, Haugen RS, Moen MH. Diagnostic delay in women with pain and endometriosis. Acta Obstet Gynecol Scand. 2003;82(7):649–53.
- Dunselman GA, Vermeulen N, Becker C, Calhaz-Jorge C, D’Hooghe T, De Bie B, et, al. ESHRE guideline: management of women with endometriosis. Hum Reprod. 2014;29(3):400-12.
- Committee on Gynecologic Practice. ACOG Practice Bulletin No. 114: Management of endometriosis. Obstet Gynecol. 2010;116(1):223–36.
- Depo-Provera CI (medroxyprogesterone acetate) [package insert]. U.S Food and Drug Administration website. Revised October 2010. Available from: https://www.accessdata.fda.gov/drugsatfda_docs/label/2010/020246s036lbl.pdf. Accessed February 10, 2020
About the Author
Breanna Failla, PharmD Candidate is in her second year of pharmacy school at Midwestern University Chicago College of Pharmacy. She serves as APhA-ASP Chapter President and Midyear Regional Meeting Coordinator for Region 4.
Article reviewed by Brooke Griffin, PharmD, BCACP