• Posted December 19, 2023

Illnesses in Childhood May Raise Odds of Childlessness Later

Remaining childless throughout adult life might be tied, in some cases, to illnesses experienced in childhood, new research suggests.

Childlessness isn't just about fertility. As a University of Oxford news release on the study noted, "multiple social, economic and individual preferences have been studied" to understand why some adults never become parents.

"Various factors are driving an increase in childlessness worldwide, with postponed parenthood being a significant contributor that potentially heightens the risk of involuntary childlessness," lead author Aoxing Liu explained in the news release.

Could certain childhood illnesses play a role?

A team led by Liu -- a postdoctoral researcher at the University of Helsinki's Institute for Molecular Medicine in Finland at the time of the study -- sought to find out.

Researchers pored over data on more than 2.5 million Finnish men and women born from 1956 through 1973. Most had finished their "reproductive years" by 2018.

Liu's group focused on about 71,500 pairs of full sisters and almost 78,000 pairs of full brothers, where one sibling was childless and the other had had one or more kids.

The study found that 1 of every 4 men in the Finnish cohort were childless by 2018, compared 16.6% of the women. Education emerged as a prime factor in childlessness, with less-educated Finns less likely to have kids, according to the study.

But certain illnesses of childhood also appeared to raise the odds for adult childlessness. Looking over 414 early-life diagnoses, 74 were significantly linked to whether or not a child would grow up to become a childless adult.

About half were classed as "mental-behavioral" disorders, Liu's team said. But effects varied by sex -- for example, schizophrenia and a history of acute alcohol intoxication in childhood were more strongly associated with childlessness in men than women, the study found.

Non-psychiatric illnesses or conditions of childhood also played a role in being childless later on. For women, obesity diagnosed in a girl's teen years, rather than later on, was associated with high odds of becoming childless.

Diabetes-related diseases in childhood as well as birth defects had stronger associations for childlessness among women than men.

Diagnoses of autoimmune and inflammatory diseases in early life appeared to up risks for childlessness generally.

What's the link? According to the news release, "the absence of a partner played a substantial role in the connection between diseases and childlessness, accounting for an estimated 29.3% in women and 37.9% in men." People who went through life without children were twice as likely to be single as those who had had kids, the study found.

And among people who were partnered, six different childhood illnesses in women, and 11 in men, appeared linked to being childless, the Finnish group found.

Senior author Andrea Ganna said the study "paves the way for a better understanding of how disease contributes to involuntary childlessness and the need for improved public health interventions." Ganna is group leader at the University of Helsinki's Institute for Molecular Medicine in Finland.

His team acknowledged that more data is needed to determine which people were childless by choice and which were involuntarily childless due to infertility or other life factors.

The study was published Dec. 18 in Nature Human Behavior.

More information

The Institute for Family Studies has more about the rise of childlessness in America.

SOURCE: University of Oxford, news release, Dec. 18, 2023