Older women are more likely to give birth to bigger babies, while smaller newborns are more common among younger moms, Dutch researchers say.
Prior studies have hinted at links between a mother's age and her baby's birthweight, as well as potential health consequences when babies are very small or very large. Babies who grow less than expected in the womb have a higher risk of birth complications, as well as diabetes and heart disease in adulthood. Very large newborns may be more likely to become obese later in life.
This could be particularly relevant as the age at which women are having children is still increasing in the Western world. For example, according to a 2010 study by the Pew Research Center, the percentage of U.S. babies being born to women older than 35 went from 9 percent in 1990 to 14 percent in 2008.