CONTEXT: Previous male contraceptive studies showed that progestins enhance spermatogenesis suppression by androgens in men. OBJECTIVE: We compared the efficacy of spermatogenesis suppression by the combination of levonorgestrel (LNG) with testosterone (T) implants to that by T implants alone in two different ethnic groups. DESIGN: This was a randomized trial performed in two centers with two treatment groups. SETTINGS: The study was performed at the Academic Medical Center in the United States and the Research Institute in China. PARTICIPANTS: Forty non-Chinese and 40 Chinese healthy male volunteers were studied. INTERVENTIONS: Subjects were randomized to receive four LNG implants together with four T implants (inserted on d 1 and wk 15-18) vs. T implants alone for 30 wk. MAIN OUTCOME MEASURES: The primary end point compared the efficiency of suppression to severe oligozoospermia (1 x 10(6)/ml) by LNG plus T implants vs. that by T implants alone. The secondary end point examined differences in spermatogenesis suppression between Chinese and non-Chinese subjects. RESULTS:LNG plus T implants caused more suppression of spermatogenesis to severe oligozoospermia during the treatment period than T implants alone at both sites (P < 0.02). In Chinese men, severe oligozoospermia was achieved in more than 90% of the men in both treatment groups. Suppression to severe oligozoospermia was less in the non-Chinese men (59%) after T alone (P < 0.020); this difference disappeared with combined treatment (89%). T implant extrusion occurred in six men. Acne and increased hemoglobin were the most common adverse events. CONCLUSION: T implants resulted in more pronounced spermatogenesis suppression in Chinese men. Addition of LNG implants to T implants enhanced the suppression of spermatogenesis in the treatment period in both Chinese and non-Chinese men.
RCT Entities:
CONTEXT: Previous male contraceptive studies showed that progestins enhance spermatogenesis suppression by androgens in men. OBJECTIVE: We compared the efficacy of spermatogenesis suppression by the combination of levonorgestrel (LNG) with testosterone (T) implants to that by T implants alone in two different ethnic groups. DESIGN: This was a randomized trial performed in two centers with two treatment groups. SETTINGS: The study was performed at the Academic Medical Center in the United States and the Research Institute in China. PARTICIPANTS: Forty non-Chinese and 40 Chinese healthy male volunteers were studied. INTERVENTIONS: Subjects were randomized to receive four LNG implants together with four T implants (inserted on d 1 and wk 15-18) vs. T implants alone for 30 wk. MAIN OUTCOME MEASURES: The primary end point compared the efficiency of suppression to severe oligozoospermia (1 x 10(6)/ml) by LNG plus T implants vs. that by T implants alone. The secondary end point examined differences in spermatogenesis suppression between Chinese and non-Chinese subjects. RESULTS:LNG plus T implants caused more suppression of spermatogenesis to severe oligozoospermia during the treatment period than T implants alone at both sites (P < 0.02). In Chinese men, severe oligozoospermia was achieved in more than 90% of the men in both treatment groups. Suppression to severe oligozoospermia was less in the non-Chinese men (59%) after T alone (P < 0.020); this difference disappeared with combined treatment (89%). T implant extrusion occurred in six men. Acne and increased hemoglobin were the most common adverse events. CONCLUSION: T implants resulted in more pronounced spermatogenesis suppression in Chinese men. Addition of LNG implants to T implants enhanced the suppression of spermatogenesis in the treatment period in both Chinese and non-Chinese men.
Authors: Micol S Rothman; Nichole E Carlson; Mei Xu; Christina Wang; Ronald Swerdloff; Paul Lee; Victor H H Goh; E Chester Ridgway; Margaret E Wierman Journal: Steroids Date: 2010-11-09 Impact factor: 2.668
Authors: Alissa Renne; Lindi Luo; Jonathan Jarow; William W Wright; Terry R Brown; Haolin Chen; Barry R Zirkin; Marlin D Friesen Journal: J Androl Date: 2011-10-20
Authors: Vahid Mahabadi; John K Amory; Ronald S Swerdloff; William J Bremner; Stephanie T Page; Regine Sitruk-Ware; Peter D Christensen; Narender Kumar; Yun-Yen Tsong; Diana Blithe; Christina Wang Journal: J Clin Endocrinol Metab Date: 2009-04-14 Impact factor: 5.958
Authors: Peter Y Liu; Ronald S Swerdloff; Bradley D Anawalt; Richard A Anderson; William J Bremner; Joerg Elliesen; Yi-Qun Gu; Wendy M Kersemaekers; Robert I McLachlan; M Cristina Meriggiola; Eberhard Nieschlag; Regine Sitruk-Ware; Kirsten Vogelsong; Xing-Hai Wang; Frederick C W Wu; Michael Zitzmann; David J Handelsman; Christina Wang Journal: J Clin Endocrinol Metab Date: 2008-02-26 Impact factor: 5.958
Authors: Niloufar Ilani; Mara Y Roth; John K Amory; Ronald S Swerdloff; Clint Dart; Stephanie T Page; William J Bremner; Regine Sitruk-Ware; Narender Kumar; Diana L Blithe; Christina Wang Journal: J Clin Endocrinol Metab Date: 2012-07-12 Impact factor: 5.958