McLachlan Robert I, Robertson David M, Pruysers Enid, Ugoni Antony, Matsumoto Alvin M, Anawalt Bradley D, Bremner William J, Meriggiola Cristina
Prince Henry's Institute of Medical Research, Monash Medical Center, Clayton, Victoria 3168, Australia.
J Clin Endocrinol Metab. 2004 Jan;89(1):142-9. doi: 10.1210/jc.2003-030616.
This study aimed to establish whether the degree of suppression of serum FSH and LH was related to sperm concentration in three testosterone (T) plus progestin contraceptive regimens. We measured serum FSH and LH using a modified, highly sensitive immunofluorometric assay in samples obtained from three published studies using T enanthate (TE; 100 and 200 mg weekly) plus daily oral doses of cyproterone acetate (CPA; 5-100 mg), levonogestrel (LNG; 150-500 micro g), or desogestrel (DSG; 150-300 micro g). Overall, men with sperm concentrations below 0.1 million/ml had significantly lower gonadotropin levels (serum FSH, approximately 0.12 IU/liter; serum LH, approximately 0.05 IU/liter) than oligospermic men (sperm concentrations, 0.1-5 million/ml; serum FSH, 0.23-0.5 IU/liter; serum LH, 0.05-0.56 IU/liter), but the relationship was weak, indicating the possible existence of other determinants. Multivariate logistic regression was used to identify the influence of candidate predictors of spermatogenic effects of the T plus progestin regimens. In the LNG and DSG studies, the marked suppression of serum LH to less than 5% of baseline values (<0.15 IU/liter) was a consistent and highly significant predictor of sperm concentration (reduced to 2-7% that seen at higher LH levels) and the likelihood of its suppression below 1 million/ml (a proposed threshold for contraceptive efficacy). Serum FSH was not a significant independent predictor. The use of DSG and CPA (but not LNG) was a significant independent predictor of sperm suppression, and regimens that contained 200 mg TE weekly caused less spermatogenic suppression than 100 mg TE weekly. These findings suggest that T-progestin contraceptive regimens suppress sperm concentration by gonadotropin-dependent and -independent mechanisms. The suppression of serum LH is a major predictor of the suppression of sperm concentration suppression in the LNG and DSG treatment studies. On the other hand, the greater spermatogenic suppression in regimens containing DSG or CPA suggests that these progestins have additional actions to suppress spermatogenesis via a gonadotropin-independent mechanism(s)
本研究旨在确定在三种睾酮（T）加孕激素避孕方案中，血清促卵泡生成素（FSH）和促黄体生成素（LH）的抑制程度是否与精子浓度相关。我们使用改良的高灵敏度免疫荧光测定法，对从三项已发表研究中获取的样本进行血清FSH和LH测定，这三项研究分别使用庚酸睾酮（TE；每周100和200毫克）加每日口服醋酸环丙孕酮（CPA；5 - 100毫克）、左炔诺孕酮（LNG；150 - 500微克）或去氧孕烯（DSG；150 - 300微克）。总体而言，精子浓度低于100万/毫升的男性，其促性腺激素水平（血清FSH约为0.12国际单位/升；血清LH约为0.05国际单位/升）显著低于少精子症男性（精子浓度为0.1 - 500万/毫升；血清FSH为0.23 - 0.5国际单位/升；血清LH为0.05 - 0.56国际单位/升），但这种关系较弱，表明可能存在其他决定因素。采用多变量逻辑回归分析来确定T加孕激素方案对生精作用的候选预测因素的影响。在LNG和DSG研究中，血清LH显著抑制至低于基线值的5%（<0.15国际单位/升），是精子浓度（降至LH水平较高时的2 - 7%）及其抑制至低于100万/毫升（避孕效果的建议阈值）可能性的一致且高度显著的预测因素。血清FSH不是显著的独立预测因素。使用DSG和CPA（而非LNG）是精子抑制的显著独立预测因素，每周使用200毫克TE的方案比每周使用100毫克TE的方案引起的生精抑制作用更小。这些发现表明，T - 孕激素避孕方案通过促性腺激素依赖和非依赖机制抑制精子浓度。在LNG和DSG治疗研究中，血清LH的抑制是精子浓度抑制的主要预测因素。另一方面，含DSG或CPA方案中生精抑制作用更强，表明这些孕激素通过促性腺激素非依赖机制具有额外的抑制生精作用。
