Objective: To evaluate the relationship between seminal leukocytes and abnormal semen parameters in a large population of infertility patients.
Design: Prospective clinical study.
Setting: Center for Reproductive Medicine at Brigham and Women's Hospital, Boston, Massachusetts.
Patient(s): One thousand seven hundred ten male partners in infertile couples attending the Center for Reproductive Medicine.
Main outcome measure(s): Seminal leukocyte concentrations, sperm count, motility and morphology, and the prevalence of samples with < 10 x 10(6) motile sperm per ejaculate (a parameter defined by IVF as the most clinically significant predictor of male infertility).
Result(s): There was a strong relationship between increasing leukocyte concentrations in semen and abnormal semen parameters. Statistically significant differences in sperm concentrations and morphology were observed at leukocytospermia thresholds of 5 x 10(5) and 2 x 10(6) granulocytes/mL, respectively. The percentage of suboptimal semen specimens as defined by IVF criteria (< 10(7) total motile sperm per ejaculate) significantly increased with increasing seminal granulocyte concentrations. A twofold increased prevalence in such suboptimal semen specimens was observed at the leukocytospermia threshold of 2 x 10(6) granulocytes/mL.
Conclusion(s): There is a relationship between increasing seminal granulocyte concentrations and poor semen parameters. At seminal granulocyte concentrations > 2 x 10(6)/mL, semen parameter abnormalities were observed that were both statistically and clinically significant.