US STUDY OF SEMEN QUALITY IN PARTNERS OF PREGNANT WOMEN

来自多个来源的数据支持不断变化的环境 男性生殖功能下降，包括据报告 在过去的五十年里，世界范围内的精液质量下降。 精子密度的地理差异也很大， 报道 然而，要清楚地识别真实的地理和时间 精液质量的差异，仔细控制精液的研究 收集和分析方案，种群选择，以及 必须首先进行混淆。 这些对照研究， 应在任何试图确定造成暂时性的环境原因之前， 和精液质量的地理差异，尚未进行。 因此，我们建议对精液进行多中心研究， 孕妇配偶男性生殖功能的血清标志物 女性，从美国四个城市中心招募。 这项拟议的研究 将构成国际研究的美国部分， 设计，开始于1996年11月在四个欧洲城市。 协议和 欧洲使用的调查表将根据需要进行最低限度的调整 对于美国人来说。 精液的形态和活力分析 所有美国中心将由一名技术人员在 加州大学男科协调中心戴维斯，所有幻灯片将被重读 由男科协调中心的一名技术人员进行形态学研究 在巴黎的中心。 血清分析将由 《生长与繁殖》，哥本哈根，美国免费研究。 在欧洲已经建立了严格的质量控制程序， 将在美国的所有中心使用， 男科协调中心。 我们研究的主要目的是 是估计精液参数的地理变异性， 美国和8个欧洲和美国城市。 我们的次要目标 是研究血清激素（睾酮， 促黄体生成素，促卵泡激素，性 激素结合球蛋白和雌二醇），以及睾丸和其他 身体异常，以及这些结果与 精液质量 最后，为了评估健康后果， 这种可变性，我们建议评估关系的强度 这些男性生殖参数和受孕时间之间的关系， 控制伴侣双方的混杂因素。 我们亦建议 建立一个男性参与者登记册，研究男性参与者的变化， 生殖生物标志物在精液和血清中的前瞻性， 用于暴露生物标志物测定的血清和精液样本 及效果 国际指导委员会，由研究 来自欧洲和美国的调查人员，将提供指导并确保 美国和欧洲数据的可比性。 这是一个独特的机会 在可比人群中评估男性生殖的生物标志物 在美国和欧洲的多个中心，在类似的时间段， 使用共同的协议。 这项研究应提供无偏估计 城市之间的差异性，据报道， 在精液质量方面，为未来提供男性生物标志物的基线水平， 研究，并产生变异的环境原因的假设 在这些参数。

Data from several sources support a link between changing environmental exposures and decreased male reproductive function, including a reported world-wide decline in semen quality over the past fifty years. Considerable geographic variability in sperm density has also been reported. However, to clearly identify real geographic and temporal differences in semen quality, studies with carefully controlled semen collection and analysis protocols, population selection, and control of confounding must first be carried out. Such controlled studies, which should precede any attempt to identify environmental causes of temporal and geographic variation in semen quality, have not yet been conducted. We propose, therefore, to conduct a multi-center study of semen and serum biomarkers of male reproductive function in partners of pregnant women, recruited from four urban U.S. centers. This proposed study would constitute the U.S. component of an international study of this design, begun in November 1996 in four European cities. Protocols and questionnaires in use in Europe will be adapted minimally, as necessary for U.S. populations. Morphology and motility analyses of semen from all U.S. centers will be conducted by a single technician at the Andrology Coordinating Center, U.C. Davis, and all slides will be reread for morphology by a single technician at the Andrology Coordinating Center in Paris. Serum analyses will be conducted by the Department of Growth and Reproduction, Copenhagen, without charge to the U.S. study. Strict quality control procedures have been instituted in Europe and will be utilized at all U.S. centers under the supervision of the Andrology Coordinating Center. The primary aim of our proposed study is to estimate geographic variability of semen parameters both within the U.S. and among eight European and U.S. cities. Our secondary aims are to study the geographic variability of serum hormones (testosterone, inhibin-B, luteinizing hormone, follicle stimulating hormone, sex hormone binding globulin and estradiol), as well as testicular and other physical abnormalities, and the relationships between these outcomes and semen quality. Finally, in order to evaluate health consequences of this variability, we propose to assess the strength of the relationships between these male reproductive parameters and time to conception, after controlling for confounding factors in both partners. We also propose to create a registry of male participants to study changes in male reproductive biomarkers in semen and serum prospectively, and to bank samples of serum and seminal fluid for assays of biomarkers of exposure and effect. An International Steering Committee, composed of study investigators from Europe and the U.S., will provide guidance and assure comparability of U.S. and European data. This is a unique opportunity to assess biomarkers of male reproduction across comparable populations in multiple centers in the U.S. and Europe, in a similar time period, using common protocols. This study should provide unbiased estimates of variability among cities which have been reported to differ widely in semen quality, provide baseline levels of male biomarkers for future studies, and generate hypotheses of environmental causes of variation in these parameters.