This study was undertaken to evaluate the effects of a single implant containing nomegestrol acetate (Uniplant) on plasma levels of sex hormone-binding globulin (SHBG), testosterone, free testosterone, androstenedione and on blood pressure, body weight, and the development of acne vulgaris. Plasma levels of sex hormone-binding globulin, testosterone, free testosterone and androstenedione were measured. Blood pressure and body weight were determined. The development of acne vulgaris was evaluated. Total testosterone and androstenedione decreased significantly during two years of Uniplant use but all levels were within the normal range. There were no significant differences in sex hormone-binding globulin and free testosterone during 24 months of Uniplant use. All changes observed in this study were within normal range. SHBG was not affected by Uniplant use. No significant increase in androgen levels and in the development of acne vulgaris was observed in these women using nomegestrol acetate implant during two years. Based on these results, it is possible to conclude that Uniplant had no androgenic effect in women during this study.
PIP: In Bahia, Brazil, clinical researchers enrolled 18 women of reproductive age into a clinical study examining the effects of a single contraceptive implant (Uniplant) on plasma levels of sex hormone-binding globulin (SHBG), testosterone, free testosterone, androstenedione, and on blood pressure, body weight, and the development of common acne. They followed the women for 24 months. The implant consisted of silastic tubing filled with 55 mg crystalline, finely ground nomegestrol acetate. The implant did not significantly change the plasma level of SHBG (69.2 nmol/l at baseline and 59.8 nmol/l at 24 months). The plasma level of total testosterone fell from 1.9 to 1.2 nmol/l at 12 months (p 0.01) and to 0.8 nmol/l at 24 months (p 0.01) (p = 0.019 for entire study period). Yet all these levels fell within the normal range. The free testosterone plasma level did not change significantly (2.6 pmol/l at baseline and at 24 months). The plasma level of androstenedione fell steadily throughout the study period (8.7 nmol/l at baseline, 6.2 at 6 months, 4.8 at 12 months, 3.3 at 18 months, and 3.2 at 24 months; p = 0.029), probably a result of ovulation inhibition. Body weight increased from 54.7 kg at baseline to 55.3 kg at 12 months (p 0.01) and to 56 kg at 24 months. Between baseline and 12 months of Uniplant use, both systolic and diastolic blood pressure increased (p 0.01) but did not change significantly thereafter. No woman developed acne. These findings indicate that Uniplant does not induce an androgenic effect in women during two years of use.