Increased chromosome 16 disomy rates in human spermatozoa and recurrent spontaneous abortions

Objective: To investigate if unexplained recurrent spontaneous abortions (RSA) are associated with increased rates of aneuploidy in spermatozoa of RSA partners (RSA-men''). Design: Case-control study. Setting: Academic research center. Patient(s): Patients enrolled at the Hormone and Fertility Center and controls at the Department of Urology (LMU-Munich). Intervention(s): Sperm samples of 11 partners of unexplained RSA cases evaluated for elevated diploidy and disomy levels of chromosomes 1-22, X, and Y by multicolor sperm fluorescence in situ hybridization (FISH). Main Outcome Measure(s): Aneuploidy rates obtained in RSA-men compared with controls from the literature and internally; an increase of the aneuploidy rate was considered statistically significant, when it differed >= 2 standard deviations from the mean baseline level in controls. Result(s): Our sperm FISH data on RSA men showed increased disomy rates for at least three chromosomes in more than 60% of patients but no statistically significant increase of the overall mean sperm disomy or diploidy rate. In particular, meiotic errors involving chromosome 16 contributed to increased sperm disomy in more than 60% of our patients. Conclusion(s): These data suggest that among paternal meiotic errors nondisjunction of chromosome 16 might have similar relative influence on fetal aneuploidy compared with maternal chromosome 16 disomy. (C) 2015 by American Society for Reproductive Medicine.