Study Finds Summer Babies Grow up to be Healthier Adults

Researchers from the Medical Research Council (MRC) Epidemiology Unit at the University of Cambridge in the UK have found evidence that they claim supports the “fetal programming” hypothesis, which suggests that conditions during pregnancy will have long term effects on adult health. Claiming to be the “most comprehensive assessment to date of the impact of birth season on childhood growth and physical development,” the team of researchers believe the amount of sunlight the mother receives during pregnancy – or amount of vitamin D exposure experienced – is responsible for some glaring differences indentified in the study. 

Previous studies have examined the link between season of birth and birth weight, as well as the relationship between birth season (“which is indicative of in-utero vitamin D exposure“) and its effects on adult health. 

This study found that babies born in June, July and August had higher birth weight, were taller as adults, and girls born during these months started puberty later (which is linked to better health in adulthood), while the inverse was found to be true for babies born in December, January and February. Lead study author Dr. John Perry says this study is “the first to link puberty timing with seasonality,” but admits additional research needs to be done on this topic. 

Researchers analyzed data from the UK Biobank – a national health care resource – to compare the growth and developemtn of about 450,000 men and women.