Research has linked some diseases with birth month, like ADHD and having a chronically forgotten December birthday. But that doesn’t begin to compare with what Mary Regina Boland, M.D., Ph.D., and her team at the Columbia University Medical Center uncovered when they analyzed nearly 1,749,400 medical records of individuals born between 1900 and 2000. The study compared birth months to 1,688 diseases and found that birth month was significantly associated with 55 of them. However, only 19 of these disease had been previously reported on. And you thought you only had a birthday present to worry about.
Generally, babies born in October and November have the highest risk of developing diseases, compared to spring and summer babies.
But before you freak out, spring babies aren’t risk-free, and fall babies aren’t all bad either. Babies born in October were the most protected from cardiovascular diseases, followed by those with September and November birthdays. And infants born in April and May experienced the biggest multiple sclerosis risks.
Summer babies weigh more at birth, grow taller, and experience puberty later (in girls) — all signs of good health — and yet they are more likely to be nearsighted. In other words, they were this close to not being nerds.
Researchers suspect that these birth month disease risks have to do with the sun in some ways — namely, vitamin D exposure during pregnancy.
The researcher team also found that the pregnant person’s birth month can impact whether or not they have a healthy pregnancy and delivery.
Instead of obsessing over a birth month you can’t control — or worse, telling your partner to hold the baby in just a little longer — Boland advises individuals to focus on proven prenatal practices, such as a healthy diet, exercise, and prenatal vitamins (with extra vitamin D). Or, just burn your calendar.
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