Relationships Between Serum Hormone Levels and Semen Quality Among Men From an Infertility Clinic

Abstract

Participation rates in epidemiologic studies on semen quality are generally very low, raising concerns as to the potential for selection bias. Since hormones both initiate and maintain spermatogenesis, they may serve as surrogates of semen quality in epidemiologic studies. For this reason, in the present study, we explored the influence and predictive ability of reproductive and thyroid hormones on semen quality among men who were partners in an infertile couple. Between 1999 and 2003, 388 men were recruited from Massachusetts General Hospital Andrology Laboratory for clinical evaluation of fertility status. Fresh semen samples were assessed for quality (concentration, motility and morphology) and the serum levels of hormones, including follicle-stimulating hormone (FSH), luteinizing hormone (LH), inhibin B, sex hormone-binding globulin (SHBG), testosterone, free androgen index, free T4, total T3, and thyroid-stimulating hormone (TSH), were measured. Multiple logistic regression revealed increased odds for below-reference sperm concentration and morphology in men with increased FSH, and decreased odds for below-reference sperm concentration and motility in men with increased inhibin B. When FSH and inhibin B were divided into quintiles, the relationships with sperm concentration showed evidence of a threshold value. However, the ability of specific FSH (10 IU/L) and/or inhibin B (80 pg/mL) cutoff values to predict semen quality was lower than in previous reports. In multiple linear regression analysis, FSH and LH were inversely associated with sperm concentration, motility, and morphology. Inhibin B and free T4 were positively associated with sperm concentration, while there was a suggestive positive association between testosterone and sperm motility. In conclusion, we have found that FSH, LH, inhibin B, testosterone and free T4 levels are associated with human semen parameters. Additional consideration should be given to the utility of serum hormone levels as a surrogate for semen quality in epidemiologic studies in which the collection of semen is difficult due to logistical and/or volunteer rate constraints.

Clinical implications of altered thyroid status in male testicular function

“…Recently, Meeker and cols. (62) found a positive association between free T4 and sperm concentration in a group of 388 men with mean age of 36 ± 5.4 years.…”

Apoptotic sperm biomarkers and their correlation with conventional sperm parameters and male fertility potential

“…FSH may be used as a surrogate for sperm quality [31]; its combination with DNA denaturation renders the effect of DNA denaturation to predict natural pregnancy increasingly potent. In contrast to couples who conceived spontaneously or after IUI, sperm apoptotic markers in men undergoing IVF or ICSI were not predictive of pregnancy.…”

The serum inhibin B concentration and reference ranges in normozoospermia

“…However, semen quality is a surrogate of male fecundity, and a high percentage of fertile men would be classified as subnormal if sperm morphology, concentration, and motility are considered (33). Our rationale is supported by the frequent documentation of significant correlations between FSH or inhibin B levels and normal spermatogenesis (18,19,29,30,34).…”

“…The intra-and interassay coefficients of variation (CV) were !12 and !17% respectively. Since serum inhibin B concentrations were relatively constant from 1 day to another (28) and appear to decrease during the daytime (29,30), we collected a single serum sample per patient in the morning.…”