Two papers recently published in the journal Fertility and Sterility have revealed various disadvantages of increased paternal age on offspring outcomes. Paternal age has increased dramatically in the US over the past 40 years, and the trend seems to be continuing. The average age of paternity has gone from 27.4 to 30.9 years in the last 40 years.
In the 1970s, 4% of births were to fathers over the age of 40; today that number is 9%. Also in the 1970’s, one in two hundred births were to fathers over 50; today this number has doubled. Unfortunately, increased paternal age has significant implications for conception, pregnancy, and health of the offspring. The children of older men are at higher risk for genetic disorders, congenital abnormalities, neurodevelopmental disorders, and malignancies.
The American Society of Reproductive Medicine and the American Urological Association have issued joint male infertility guidelines, which include the suggestion that “Clinicians should advise couples with advanced paternal age (≥40 years) that there is an increased risk of adverse health outcomes for their offspring (3).” Spermatogonial stem cells are the cells that divide and split over a man’s lifetime to produce sperm. Spontaneous mutations occur, and then generally become present in all of a man’s sperm. It can be estimated that the sperm produced from a 25-year old male has undergone ∼350 replications, while ∼750 replications would have taken place to sustain sperm production in a 45-year old male.
The first paper, titled The Impact of Paternal Age on New Mutations and Disease in the Next Generation, explains that on average, approximately 1–2 additional mutations arise in the genome of a child per additional year in the age of the father. Thus, the number of mutations doubles with every additional 20 years of paternal age.
The second paper, titled The Risky Business of Advanced Paternal Age: Neurodevelopmental and Psychosocial Implications for Children of Older Fathers, revealed that “children, and even grandchildren, of older fathers face significantly increased incidence rates of psychiatric disease and behavioral impairment. The data do not show evidence of superior parenting behaviors among men with Advanced Paternal Age (APA). The children of men with APA are more likely to experience early bereavement, which is associated with psychological and developmental consequences. An understanding of the degree to which APA can negatively impact the offspring is imperative for patient counseling and development of practice guidelines.” They found that “offspring risks begin to emerge by a paternal age of 40 years and are formidable by a paternal age of 50 years.”
As more men are delaying having children for a number of reasons, it is reasonable for these men to consider banking their sperm. Frozen sperm are not dividing and thus are not subject to the copying errors inherent in ongoing sperm production, which increase over time.
The optimum time for this banking is subjective and unclear. However, if a man at or over 35 is projecting it will be five or more years before attempting a conception, based on previous literature and the above papers, it may be wise for him to bank his sperm. Contact us to learn more about sperm banking options available at Maze.
