Admit it: You’re secretly (or not so secretly) hoping baby looks like you. A new study found that when it comes to size, at least, the apple doesn’t fall far from the tree.
The study, led by the universities of Exeter and Bristol, determined that being overweight or obese during pregnancy causes babies to be born larger. Specifically, higher blood glucose levels are linked to higher birth weight. (On the other hand, higher blood pressure is linked to lower birth weight.) While it’s not exactly news that larger women or those who develop gestational diabetes tend to have bigger babies, this is the first study to clarify that mom’s size is actually the cause, and not other factors.
"A lot of research into pregnancy and birth weight has been based on observation, but this can make it very difficult to determine what is cause and what is effect, creating a confusing picture for mothers, clinicians and healthcare workers,” says study co-lead Dr. Jess Tyrrell. “Our genetic method is more robust, giving clear evidence that mothers' weight, glucose and blood pressure affect the size of the baby."
Researchers also explained these characteristics from mom can have big implications for baby down the road.
"Being born very large or very small can carry health risks for a newborn baby, particularly when that's at the extreme end of the spectrum,” says Dr. Rachel Freathy, another co-lead of the study. “Higher and lower birth weights are also associated with diseases such as Type 2 diabetes later on in life. Understanding which characteristics of a mother influence the birth weight of her offspring may eventually help us to tailor management of a healthy pregnancy and reduce the number of babies born too large or too small."