Could being born in the summer increase the risk of myopia?

An adolescent's season of birth could be a factor in the development of near-sightedness, a recent study suggests.

As reported in the April Ophthalmology, 276,911 Israeli-born military recruits ages 16 to 22 had overall mild, moderate, and severe myopia rates of 18.8%, 8.7%, and 2.4%, respectively. Prevalence of moderate and severe myopia was highest among participants born in June and July compared with those born in December and January. No such association was found among those with mild myopia, however.

The mechanism linking myopia and summer birth in the study cohort is not known, the researchers concluded. They suggested that light exposure during the early perinatal period might play a role.