Men who wish to father healthy children have been advised to get married and start a family before the age of 40.

In an exclusive interview with Guardian Life, Professor of Anatomy and Reproductive Endocrinology at the College of Medicine, University of Lagos, Oladapo Ashiru, said sperm quality declines with age, increasing the risk of genetic disorders in children.

“Sperm quality reduces with age. As you get older, because of environmental toxins; foods, environment, diet, occupation, they affect the sperm. Also, there is an increase in damage to the sperm DNA,” he explained.

He further stated that the decline typically becomes noticeable from age 40, adding that sperm count, motility, and morphology are all affected by ageing.

According to him, “biological changes with age, smoking, alcohol intake, unhealthy nutrition, and occupational exposure to toxins” contribute significantly to the decline in male fertility.

Ashiru’s statement comes amid a viral conversation on X, formerly Twitter, about sperm quality in older men.
A post by an X user named Queen read, “Older men are more likely to give you children with genetic mutations like dwarfism, autism, Down syndrome, and schizophrenia. Their weak sperm has a higher risk of causing mutations in kids. Try your best not to have kids with their sperm.”

Also speaking, Consultant Urologist at the Federal Medical Centre, Ebute-Metta, Lagos, Dr Apata Kehinde Omotola, said although advanced maternal age is a major factor in conditions like Down syndrome, men should also be mindful of age-related fertility risks.

“Even though it’s advisable to marry early, having children with genetic problems like Down syndrome is more of older women,” he said.

“But men are advised to marry early because the quality of sperm parameters reduces with age. Once a man is older than 50, the risk of having oligospermia (low sperm count) or azoospermia (no sperm cells at all) increases.”

He noted that other age-related health issues such as prostate enlargement, hypertension, and sexual dysfunction could also affect sperm quality and delay conception.

“By 45 years to 50 years, sperm quality starts dropping, prostate diseases start coming, and hypertension. Some antihypertensive drugs may even lead to erectile dysfunction,” he said.

“Imagine a newly wedded man battling with all these complications. How does he satisfy his partner?”
According to the Andrology Centre, while men produce sperm throughout life, both sperm count and quality decline with age, increasing the chances of infertility.

Healthline, a health information portal, also reports that sperm quality drops significantly in men over 50, citing low motility, reduced count, and poor lifestyle habits as major causes.

Speaking further, Ashiru advised men who are not yet ready to have children to consider freezing their sperm at a younger age.

He said, “It is better to freeze their sperm when they are young. Sperm preservation is the best way, just as we also give advice to women when they are in their middle 30s to freeze their eggs. We are also making the same recommendation for men.

“There is a decline in global fertility due to climate change, environmental toxins and exposures. The older you get, the more it accumulates.”