New US research has found that delaying fatherhood until later in life could have a negative effect on both children and mothers.
The new large-scale study by researchers at Stanford University looked at data on all 40,529,905 live births that took place in the US between 2007 and 2016.
After taking into account factors such as age of the mother, maternal smoking, race, education, and number of prenatal visits, the researchers found that as the age of the father increased, so did the risk of the infant being born prematurely, having a low birth weight, and requiring healthcare support after delivery such as assisted ventilation, admission to neonatal intensive care, or antibiotics.
Published by The BMJ, the study showed that children of fathers aged 45 years or more were born 0.12 weeks earlier and had a 14% higher risk of being premature (less than 37 weeks) compared to those whose fathers were aged 25 to 34 years.
These children were also born 20.2g lighter and had a 14% higher risk of low birth weight (less than 2500g) than infants born to younger fathers. They also had a 14% higher risk of being admitted to a neonatal intensive care unit and an 18% higher risk of having seizures, compared to infants with fathers aged 25 to 34 years.
Newborns of fathers aged 55 years or older also tended to score less well on the Apgar test – a test used to assess the health of a child at birth.
The team found that not only did a father’s age impact his children’s health, it also appeared to affect the mother’s health.