Your sperm also has an expiration date

It’s not just the mother’s age that matters. According to new research, men’s biological clocks are ticking, too. Older fathers may put their infants — and partners — at risk for pregnancy complications.

It’s 8 a.m. on your sisters 35th birthday and your mother has already called her three times. She wants to sleep longer, but she persists. So you call her back; she answers after the first ring.

“Sweetie,” she says, out of breath. “I was just in the kitchen making breakfast and — you won’t believe this — I cracked open an egg with two yolks inside. Do you know what that means?”

Of course you know what it means. According to modern fertility folklore, pregnancy might be on the way. But why doesn’t your mother ever call you with these brilliant fertility revelations? After all, you are 40 years old?

Older male fertility: should we be worried?

Most couples trying to conceive (and enthusiastic mothers-in-law) know that decades of research point to a woman’s age of 35 as the point in which women may begin to experience age-related pregnancy complications.

The scientific interest in women is intuitive — they play the most obvious role in the pregnancy.

Little attention, however, has been placed upon male fertility. This information gap can be rather simply illustrated by Google search data: Issues surrounding female age and fertility are Googled almost 4 times more often than male age and fertility.

According to a recent Rutgers study published in Maturitas, a medical journal covering midlife and post-reproductive health, this lack of attention is a mistake.

How a man’s clock ticks

Like women, men experience changes to their bodies and reproductive systems as they age, and this impacts their fertility and the health of their offspring.

While sperm production is unending in men, their production and transportation structures weaken over time, said Dr Matthew Lau, Consultant at the KKIVF Centre, KKH.

“For instance, the sperm production slows down and the reproductive tubes narrow. Beyond this, the prostate and urinary functions also change,” said Dr Lau.

The male sex function declines too. Over time, men’s testosterone levels dip, they experience a lower sex drive and are more susceptible to sexual problems like erectile dysfunction, said Dr Lau.

“Erectile dysfunction is closely linked to blood supply problems. When people get older, and if they have diabetes or high cholesterol levels, they are likely to have blood vessel problems. If such problems affect the penis, it leads to erectile dysfunction,” he added.

In older men, sperm quality also becomes poorer. As sperm is produced at a slower rate, the risk of exposure to toxins through factors such as infection and smoking is higher. This can damage the DNA of the sperm, said Dr Lau. If the sperm’s DNA is more than 40 per cent damaged, there is a higher chance of miscarriage, he said.

Studies have also shown that older fathers increase the risk of genetic problems such as autism and dwarfism in their children.

The study, which reviewed 40 years of research on the effects of parental age on fertility, found other links between older fathers and a variety of infant health risks.

Infants born to fathers older than 45 have a higher risk of premature birth, low Apgar scores ( based on the well-being test conducted immediately after the baby’s birth that ranks the infant based on appearance, pulse, grimace, activity and respiration) and low birth weight. They also have a higher risk of newborn seizures and late stillbirth, according to the study.

Findings presented in the study also pointed to a correlation in the presence of schizophrenia and autism in people with fathers older than 50, something that a recent study in the journal Biological Psychiatry pointed to as well, along with birth defects such as congenital heart disease and cleft palate.

Many of these issues occurred regardless of the age of female partners, who were also more likely to experience increased pregnancy complications such as gestational diabetes, preeclampsia and preterm birth after conceiving a child with an older man.

“Although it is well documented that children of older fathers are more likely to be diagnosed with schizophrenia — one in 141 infants with fathers under 25 versus one in 47 with fathers over 50 — the reason is not well understood,” said the study’s author Gloria Bachmann, director of the Women’s Health Institute at Rutgers Robert Wood Johnson Medical School in New Jersey.

What does all of this mean?

Bachmann said these findings have to do with male sperm. As people lose muscle strength and endurance with age, sperm also lose fitness over the life cycle, she said, which affects both the likelihood of conception and the prevalence of complications if conception does occur.

The definitive age in which men are more likely to negatively influence pregnancy is still unclear. According to the report, it could be anywhere from 35 to 45. But the correlation is there, and researchers are urging others to take a closer look.

“The disparity between the social interpretation of men’s and women’s fertility and role in reproduction speaks volumes regarding our assumptions about gender roles, reproduction and family planning,” the study said.

It also notes that the issues it addresses are not widely known throughout the medical and social communities and urges health care providers to alert men to the risks associated with higher paternal ages.

The scientists’ advice goes out not just to men who are considering having a baby with their wife or girlfriend: Sperm banks, the researchers pointed out, should adjust their age limits for donations, too.

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