Late paternity: sperm get older too

Christiane Fux studied journalism and psychology in Hamburg. The experienced medical editor has been writing magazine articles, news and factual texts on all conceivable health topics since 2001. In addition to her work for, Christiane Fux is also active in prose. Her first crime novel was published in 2012, and she also writes, designs and publishes her own crime plays.

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The biological clock is ticking for men too: the later they become fathers, the more often malformations and developmental disorders as well as pregnancy complications occur in children. The latter also endanger the mothers. The negative effect is noticeable from the age of 45 onwards.

For a long time the matter seemed clear: while women have a supply of egg cells at birth - they then age, men produce millions of new sperm every day in the course of their lives. “It was therefore assumed that male germ cells would not age,” explains Prof. Stefan Schlatt, Director of the Center for Reproductive Medicine and Andrology at the University Hospital in Münster.

The genome of the germ cells changes

But this assumption is outdated: In men, too, genetic defects occur more frequently with advancing age. A sperm-forming stem cell in a 50-year-old has already had several hundred divisions. And with each of them comes the risk of genetic defects.

The genes themselves are partially changed. So-called epigenetic changes are also sometimes the problem. They influence which genes in the genome are active or muted - this is often an unfavorable constellation in an unhealthy lifestyle. "This can affect both embryonic and placenta development," says Schlatt.

The consequences are manifold, shows a US study. The researchers evaluated the data from more than 40.5 million live births between 2007 and 2016. In addition to various personal details such as social origin, school education, nationality, they also recorded the age of the mothers and fathers.

Difficult start in life

The result shows that pregnancies with older fathers were particularly often the most unfavorable. Compared to children whose fathers were between 25 and 34 years of age at conception, children of fathers who were 45 years of age or older were at higher risk of being born prematurely or too easily. The infants also required respiratory support significantly more often after birth or had to go to the intensive care unit more often.

Higher risk of gestational diabetes

For the mothers, too, the age of the fathers is not without consequences. The likelihood of developing gestational diabetes increased by 28 percent in a partner between the ages of 45 and 54 and by 34 percent in a partner aged 55 and over. The high blood sugar levels not only harm the mother, they can also affect the child if they are not properly controlled.

The all-clear was given for the serious complications of pregnancy, preeclampsia and eclampsia. They were not increased for mothers with older partners.

Autism and schizophrenia

“This study makes it clear that a higher age of the father favors complications in the child and the mother. Previous studies have shown that diseases such as autism and schizophrenia are also related to the age of the father, ”adds Schlatt.

Couples wishing to have children should be advised that the higher the father's age, the lower the quality of the sperm and the higher the risk of other age-related risk factors, according to experts. Men who want to take their time with fathering might consider freezing their sperm before age 40.

Press release: DGE Congress: Sperm also age - late fatherhood carries risks for mother and child, 03/18/2019

Tags:  desire to have children menshealth pregnancy birth