Effect of oral contraceptives containing estradiol and nomegestrol acetate or ethinyl-estradiol and chlormadinone acetate on primary dysmenorrhea

Objective: To study the three cycles effect on primary dysmenorrhea of the monophasic 24/4 estradiol/nomegestrol acetate (E2/NOMAC) and of the 21/7 ethinyl-estradiol/chlormadinone acetate (EE/CMA) oral contraceptive. The tolerability and the effect of both preparations on metabolism and health-related quality of life were also evaluated. Design: Prospective observational cohort study. Setting: Tertiary gynecologic center for pelvic pain. Patients: Subjects with primary dysmenorrhea requiring an oral contraceptive, who spontaneously selected either E2/NOMAC (n¼20) or EE/CMA (n¼20). Main outcome measures: Visual Analogue Scale (VAS) score for dysmenorrhea, Short Form-36 questionnaire for health-related quality of life, lipoproteins and days of menstrual bleeding (withdrawal bleeding during oral contraceptive). Results: Mean age and body mass index (BMI) were similar between the two groups. The final analysis was performed on 34 women, 15 in E2/NOMAC and 19 in EE/CMA group. Compliance with treatment was significantly higher with EE/CMA (100%) than E2/NOMAC (75%) (p¼0.02). Both treatments significantly (p50.0001) reduced VAS of primary dysmenorrhea, similarly (E2/NOMAC by a mean of 74.7%, EE/CMA by a mean of 78.4%; p¼0.973). Only E2/NOMAC significantly increased SF-36 score (p¼0.001), both in physical (p¼0.001) and mental domains (p¼0.004). The mean number of days of menstrual bleeding was significantly reduced in E2/NOMAC group (from 4.86 ± 1.20 d to 2.64 ± 1.59 d, p¼0.0005 versus baseline, p¼0.007 versus EE/CMA group). BMI did not vary in either group. E2/NOMAC did not change lipoproteins and apoproteins while EE/CMA increased total cholesterol (p¼0.0114), HDLcholesterol (p¼0.0008), triglycerides (p¼0.002), apoprotein-A1 (Apo-A1; p¼0.0006) and apopoprotein-B (Apo-B; p¼0.008), decreasing LDL/HDL ratio (p¼0.024). Conclusions: Both oral contraceptives reduced similarly primary dysmenorrhea, with E2/NOMAC also reducing withdrawal bleedings and being neutral on lipid metabolism.