Relationship between sperm characteristics and hormonal parameters in normal couples

Objective: To examine the relationships between hormone profiles and semen analysis measures and fertility in the male partners of presumed normal couples. Design: Prospective clinical study. Setting: Healthy volunteers in an academic research environment. Patient(s): One hundred forty-five reproductive age couples without known risk factors for infertility and who had discontinued contraception to achieve pregnancy completed this component of this study. Each couple was followed for less than or equal to12 menstrual cycles while they attempted to conceive. Intervention(s): Semen quality measures for the first ejaculates were obtained at the start of the study along with a single blood sample. Levels of FSH, bioactive FSH, inhibin 13, LH, and T were measured for each man. Main Outcome Measure(s): Semen analysis, FSH, inhibin B, LH, T, and clinical pregnancy. Result(s): Significant positive relationships were observed between the two measures of FSH as well as between both of the FSH measures and LH. Follicle-stimulating hormone as measured by RIA was significantly negatively correlated with inhibin B. Inhibin B showed a marginally significant negative correlation with LH, and LH and T had a marginally significant positive correlation. Inhibin B increased significantly, and both measures of FSH activity showed significant decreases, with increasing levels in several semen quality measures. There was no significant relationship between the measured hormones and the pregnant and nonpregnant groups or time to pregnancy. Conclusion(s): These results contribute additional information on the utility of reproductive hormone measurements for predicting semen quality in couples without known reduced fertility.