Endometriosis is a chronic condition characterized by the growth of endometrial glands and stroma outside the endometrial cavity. In the adolescent population, endometriosis is considered to be the leading cause of secondary dysmenorrhea,1 with a prevalence of at least 70% in those presenting for laparoscopic investigation.2 In addition to its high prevalence, endometriosis can significantly impact those affected, leading to severe deficits in quality of life and absenteeism in school and activities.3,4 Symptoms of endometriosis include chronic pelvic pain and dysmenorrhea.

Hormonal therapy is advised for endometriosis, as it has been shown to potentially mitigate symptom recurrence and disease progression in adolescents.5 First-line hormonal therapy for endometriosis includes combined hormonal contraceptives (oral, vaginal ring, or transdermal) and progestin-only therapies (oral, injection, subdermal implant, intrauterine device). An adolescent's choice of hormonal treatment is influenced by multiple factors, including the efficacy, tolerability, and formulation of the method, any potential contraceptive and non-contraceptive benefits, and medical co-morbidities that may be contraindications to select methods, namely estrogen-containing treatments.6

The drospirenone-only (DRSP) 4 mg oral contraceptive is a relatively new contraceptive approved by the United States Food Drug Administration in 2019.7 This hormone administration regimen includes 24 days of DRSP followed by a four-day placebo period. Unlike its earlier progestin-only counterpart, norethindrone 0.35 mg,8 DRSP consistently suppresses ovulation and maintains ovulation inhibition even with a 24-hour delay.9 As a result, clinical trials have demonstrated high contraceptive efficacy and a favorable bleeding pattern.10 Little is known, however, about its potential efficacy for other non-contraceptive indications, including endometriosis. As endometriosis is a highly prevalent disease that can lead to debilitating pain and impaired quality of life in adolescents, increasing the array of effective and well-tolerated hormonal treatments is greatly needed. A wider variety of treatments could help patients achieve different adjuvant goals in addition to pelvic pain, including management of acne, contraception, and other hormonal effects. The purpose of this study was to evaluate the efficacy, tolerability, and adverse effects of continuous DRSP (taken without placebo) in adolescents and young adults with endometriosis. We hypothesized that continuous DRSP would be a well-tolerated and helpful treatment for endometriosis-associated symptoms.