Relationships between serum hormone levels and semen quality among men from an infertility clinic.

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.

The relationship between human semen characteristics and sperm apoptosis: a pilot study.

This work was undertaken to explore the association between human semen characteristics and apoptosis in ejaculated sperm. We collected semen samples from 23 consecutive male patients who presented to the Andrology Laboratory at Massachusetts General Hospital (MGH) for routine semen analysis. Sperm concentration and motility were measured using computer-assisted sperm analysis.

Does the potential for selection bias in semen quality studies depend on study design? Experience from a study conducted within an infertility clinic.

Background: The low participation rates in human semen quality studies raises concern for the potential of differential participation based on semen quality (or a surrogate). To explore the potential for differential participation, we compared semen analysis results from study subjects with those of non-study subjects.

Methods: We obtained semen analysis results from 235 study subjects and retrospectively obtained results from a subset of 235 infertility clinic patients that were not study subjects but met the same eligibility criteria.

Impact of seasonal variation, age and smoking status on human semen parameters: The Massachusetts General Hospital experience.

BACKGROUND: To investigate the relationship of human semen parameters with season, age and smoking status. METHODS: The present study used data from subjects recruited into an ongoing cross-sectional study on the relationship between environmental agents and semen characteristics. Our population consisted of 306 patients who presented to the Vincent Memorial Andrology Laboratory of Massachusetts General Hospital for semen evaluation.

Medications as a source of human exposure to phthalates.

Phthalates are a group of multifunctional chemicals used in consumer and personal care products, plastics, and medical devices. Laboratory studies show that some phthalates are reproductive and developmental toxicants. Recently, human studies have shown measurable levels of several phthalates in most of the U.