- New study links paternal age to birth risks.
- The risk is directly proportional to the age of the father: the older he is, the higher the risk.
- Babies born to fathers older than 35 are at a greater risk of adverse birth outcomes like seizures and low weight.
In the United States, the age at which couples have children is continuously increasing. Nearly 10% of babies are born to fathers over 40 years old. 40 years ago, the number was only 4%.
Recently, a team of researchers at the Stanford University School of Medicine conducted a study, in which they linked infants of older fathers with multiple increased risks at birth. They analyzed a massive amount of data (over 40.5 million births) recorded between 2007 and 2016 in the United States.
The study shows that the father’s age can also affect the mother’s health during pregnancy: it can increase the risk of developing gestational diabetes and pre-eclampsia. Overall, giving birth to a healthy baby depends on both mother and father, and this research mainly focuses on how paternal age is associated with perinatal outcomes.
Age Versus Risk
As per the 40.5 million birth data, babies born to fathers older than 35 are at a greater risk of adverse birth outcomes like seizures, low weight, and sometimes they need immediate ventilation after birth.
The risk is directly proportional to the age of the father: the older he is, the higher the risk. For instance, men who were above 45 had 14% more chance of having an infant born prematurely, while men older than 50 had 28% more chance of having a baby that required an intensive care nursery.
The researchers arranged the data according to the father’s age. They made 5 subsets:
- father younger than 25
- from age 25 to 34
- 35 to 44
- 45 to 55
- above 55
They considered all those factors that could alter the relationship between the men’s age and birth outcomes, for example, race, marital status, level of education, access to hospitals, and smoking habits.
The data showed that once a father becomes 35 years old, the birth risks increases slightly. As he gets older, year by year, he accumulates 2 new mutations (on average) in the sperm DNA. However, the number increases sharply for men of the subsequent age tier.
Image credit: Florence & Rae/Flickr
The men’s age also affects their partner’s health. For fathers older than the age of 45, mothers had 28% more chances of developing gestational diabetes, compared to younger fathers from age 25 to 34. The exact reason behind this is still unclear, but researchers suspect that the female’s placenta plays a major role here.
No Need To Drastically Change Your Life Plans
The risks are still comparatively low, so people shouldn’t drastically change their life plans by just seeing these numbers. To explain in a better way, researchers compared these scenarios with purchasing lottery tickets.
If someone purchases two lottery tickets rather than one, his chances of winning get double. However, this is a 100% relative increase. Since the probability of actually winning the lottery was very low in the first place, it is still unlikely that the person is going to win.
The researchers see this study as a way to educate people and health officials. They plan to analyze the data of other countries to confirm the relations between men’s age and birth risks, and to find the biological mechanisms behind these associations.