Whoa, baby.
They say kids can age you — and new research out of Finland shows how the number of babies a woman has can even shorten her lifespan.
It turns out not only is there a sweet spot for family expansion that potentially lessens mom’s risk of an early death, but her kiddos could also slow aging.
Pregnancy brings on a multitude of changes for the mother, including extending biological age (the age of our cells and organs) for those who conceive between 24 and 38 years old.
However, the number of children can also affect a woman’s chronological age, or the number of years she has been alive.
A study from the University of Helsinki and the Minerva Foundation Institute for Medical Research found that giving birth to more than the average number of children (around two to three) at all has been linked to a shorter lifespan and faster biological aging.
The study looked at nearly 15,000 Finnish twins who had completed a questionnaire in 1975 and had their life course followed up to the present.
Those who had an average of 6.8 children had the highest mortality risk and an increase in biological aging.
Meanwhile, women who had 2 to 2.4 children had the slowest aging and longest lifespan on average.
But it’s not just those who have kids that are affected, as women who didn’t deliver children also fared worse in terms of increased mortality risk and biological aging.
The age at which women experienced childbirth also had an impact, as those who had children early in life also showed signs of faster biological aging and shorter lives.
Previous research has also found that being pregnant can age a woman about two years, but giving birth may reverse biological age by eight years, according to a study from the Yale Child Study Center published in Cell Metabolism.
“A person who is biologically older than their calendar age is at a higher risk of death,” study lead Miina Ollikainen said in a press release. “Our results show that life history choices leave a lasting biological imprint that can be measured long before old age.”
The research team also theorizes that evolution may play a role in the link between how many children a woman gives birth to and her lifespan.
They believe these results came about as natural selection may favor reproduction at a younger age for shorter generation timespans — even if it comes at a cost to the mother’s health as she ages.
However, the researchers also pointed out that a variety of factors can affect biological aging and lifespan.
They also noted that their findings only show an association, not a direct cause-and-effect relationship, and therefore shouldn’t have a significant impact on reproductive plans.
“An individual woman should therefore not consider changing her own plans or wishes regarding children based on these findings,” said Ollikainen.
