Childhood obesity cuts women’s chances of becoming mums
Girls who are overweight from primary school age are significantly less likely to have children as adults, according to new research
Girls who are overweight or obese from as young as six years old could face a much lower chance of becoming mothers later in life, new research suggests
Scientists found that women who followed the highest body mass index (BMI) trajectory throughout childhood were up to 42 per cent less likely to have children by their mid-30s than those who maintained a healthy weight
Researchers say the findings suggest fertility may be influenced far earlier in life than previously believed and highlight the importance of tackling childhood obesity
The Danish study analysed data from 60,864 women born in Copenhagen between 1950 and 1989, using yearly school health records to track height and weight before linking them to birth records
Overall, 78 per cent of the women went on to have children between the ages of 18 and 45, while 22 per cent remained childless (13,195)
After accounting for factors including relationship status, women who were obese from childhood were 22 per cent less likely to have a child between the ages of 25 and 29 than women with a healthy childhood BMI
Between the ages of 30 and 34, their chances of giving birth were 42 per cent lower
Girls who were overweight, rather than obese, also faced reduced fertility, with their odds of having a child falling by nine per cent between 25 and 29 years old and by 26 per cent between 30 and 34
Lead author Dr Dorthe Pedersen, of Copenhagen University Hospital, said: “Our findings suggest that less favourable BMI patterns from as young as six years old may increase a woman’s risk of childlessness from their mid-20s onwards
“By the time women reach their 30s, when many women start trying to conceive and fertility difficulties often become evident, the effects on reproductive capacity may already be established, underscoring the importance of preventive efforts focused on healthy growth and development in childhood.”
She added: “Although advancing age is a major driver of childlessness, with postponed parenthood being a substantial contributor, overweight and obesity appear to further increase these risks through physiological and social pathways, possibly including effects on egg quality and hormonal disturbances
“So it is concerning that one in three school-aged girls in Europe are currently living with overweight or obesity.”
Senior author Dr Jennifer Baker, also from Copenhagen University Hospital, said: “Our study paves the way for a better understanding of how overweight and obesity during childhood may contribute to involuntary childlessness
“More broadly, our findings suggest that reproductive health has much earlier origins than is commonly appreciated
“We need to be thinking of infertility as a cumulative physical and social experience, with effects beginning many years before women wish to become pregnant
“Recognising these early-life influences could reshape how we understand reproductive health and identify opportunities to support it long before family planning begins.”
The researchers, whose findings were published in JAMA Network Open, stressed the study shows an association rather than proving childhood obesity directly causes infertility and said further research is needed
