Philadelphia, PA- Utah researchers presented a study today at ASRM’s 75th Scientific Congress and Expo showing that there is a relationship between a man’s total motile sperm count (TMC) as a marker of fertility, and the number of offspring his ancestors had through several generations. The better an individual’s TMC, the more children his ancestors had.
The researchers used the Utah Population Data Base (UPDB) in this retrospective, population-based cohort analysis to identify men who had a measured TMC on record in addition to complete pedigree information going back to 1935 or earlier (1935, in order to reduce the effect of contraception on the results). The average number of generations in the family and the average number of offspring per generation were identified for each individual for the time period 1935 and earlier, and separately for the years after 1935. Statistical techniques were used to analyze the relationship between intergenerational family size, in and prior to 1935, as it related to individuals’ TMCs.
Total Motile Sperm Count was obtained for 2,182 men. The 25th percentile for TMC included 541 men and 112 men made up the 5th percentile, those with the poorest sperm parameters, including azoospermia. The average number of generations prior to 1935 in an individual pedigree was 3.6, with an average of 6.5 offspring per generation in that time period.
When TMC was input as a continuous variable, statistical analysis suggested that lower TMC is related to smaller family size across the generations. Going back nine generations, the researchers observed that, for each additional child in the family, a subject’s TMC increased by 1.88 million.
ASRM President Peter Schlegel, MD noted, “This study, one of the first of its kind, uses big data in an innovative way to identify a marker of male infertility associated with family size over generations. It shows us a clear picture of how male fertility may be inherited. Although it would seem paradoxical that male infertility is inherited, these observations strongly suggest an inherited pattern of infertility as well as the potential for de novo genetic changes that have already been described.”
O-56 Patel et al, “Lower Total Motile Count is Associated with Smaller Historic Intergenerational Family Size: A Pedigree Analysis from the Utah Population Database”
ASRM is a multidisciplinary organization dedicated to the advancement of the science and practice of reproductive medicine. The Society accomplishes its mission through the pursuit of excellence in education and research and through advocacy on behalf of patients, physicians, and affiliated health care providers. The Society is committed to facilitating and sponsoring educational activities for the lay public and continuing medical education activities for professionals who are engaged in the practice of and research in reproductive medicine. www.asrm.org