Do men have a biological clock? The best age to become a father

A man holding a child

A man holding a new-born baby. Scientific studies are increasingly revealing that men, too, should worry about ageing when it comes to bearing children.

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The weekend was flooded with hearty messages about Father’s Day. Different generations of men were celebrated for their roles as fathers.

Oftentimes, when the phrase “your biological clock is ticking” is used, many think of a woman who should worry that she is getting too old to have a baby.

However, scientific studies are increasingly revealing that men, too, should worry about ageing when it comes to bearing children.

Studies have found that the number and quality of the sperm decline with age, and from a biological standpoint, experts recommend a man is best suited to fatherhood from his late 20s to early 30s.

Men often think that their age doesn’t matter when it comes to having a child and the biological clock is important only for women.

According to the Guinness World Records, the oldest man to father a child was 92 years old at the time of the birth. Still, researchers have found that a man’s age can affect a couple’s chances of becoming pregnant.

Most fertile age

Research published in the Journal of Epidemiology & Community Health found that the age when a man is most fertile is between 22 and 25 years.

It is suggested that men have children before the age of 35. After this, male fertility begins to wane, and the sperm might result in pregnancies where mutations occur.

Further, if the man is above 45 years, the chances of having a miscarriage are much higher, irrespective of the age of the pregnant woman.

While a man essentially never stops producing sperm, as he ages, his sperm undergoes genetic mutations, which increases the likelihood that the DNA of his sperm may be damaged. This can influence fertility and also create potential impacts on the health of his future children.

Studies have shown that fathers with an advanced paternal age may be more likely to have children with neurodevelopmental disorders. A study done in 2010 observed the offspring of men over 40 had a five-fold risk of developing Autism Spectrum Disorder compared to the general population.

Semen parameters

The WHO has set semen parameters which are benchmarks for healthy sperms to include shape (morphology) and movement (motility).

Sperm health can depend on various factors that influence fertility. In terms of quantity, fertility is most likely if the semen discharged in a single ejaculation contains at least 15 million sperm per millilitre.

Too little sperm in an ejaculation might make it more difficult to get pregnant.

When it comes to sperm motility, pregnancy is possible with less than 40 per cent of the sperm in ejaculate moving — 40 per cent being the threshold since the higher, the better chances of fertility. From around age 35, men may see their semen parameters getting worse.