Levonorgestrel effects on serum androgens, sex hormone-binding globulin levels, hair shaft diameter, and sexual function

Objective: To determine the effects of levonorgestrel (LNG) on serum androgens, sex hormone binding globulin (SHBG), hair shaft diameter, and sexual function in women. Design: Substudy of a prospective randomized double-blind study in women using an LNG SC implant (LNG-SI), who were treated with doxycycline or placebo. Setting: Medical school department of obstetrics and gynecology. Patient(s): Forty women were enrolled; 36 completed the study. Intervention(s): Participants were randomized to doxycycline 20 mg or an identical placebo orally twice a day after LNG-SI insertion. Main Outcome Measure(s): Serum levels of total T (TT), free T (FT), androstenedione (A), dehydroepiandrosterone sulfate (DHEAS), dihydrotestosterone (DHT), androstanediol glucuronide (AG). SHBG, and LNG; hair shaft diameter; and sexual function using the Brief Index of Sexual Function for Women and the Arizona Sexual Experiences Scale were assessed. Result(s): Serum TT, A, DHT, DHEAS, and SHBG declined after LNG-SI insertion. No changes were found in FT. AG, hair shaft diameter, or sexual function. Serum LNG correlated with SHBG levels. There were no differences between the placebo and doxycycline groups. Conclusion(s): LNG reduced serum TT, A, DHT, DHEAS, and SHBG but had no effect on sexual function or markers of androgen bioactivity. (Fertil Steril (R) 2010;93:1997-2003. (C)2010 by American Society for Reproductive Medicine.)