Month of birth is linked to risk of multiple sclerosis

In the northern hemisphere, multiple sclerosis is more common in people born in May and less common in those born in November. Willer and colleagues (p 120) analysed the birth months of 42 045 people with multiple sclerosis from Canada, Great Britain, Denmark, and Sweden. Compared to predictions, 8.5% fewer people with multiple sclerosis were born in November and 9.1% more in May. The correlation was greater in countries with a higher prevalence of multiple sclerosis.

Credit: CHARLES WALKER/TOPFOTO