Our tendency to worry apparently has a gender bias: Researchers at the University of Cambridge analyzed studies on anxiety from around the world and found women were twice as likely to experience anxiety as men.

For their “review of reviews”—published in the the journal Brain and Behavior this week—the paper’s authors looked at 1232 reviews on the prevalence of anxiety; after eliminating duplicates and reviews that didn't meet their study criteria, they were left with 48 to analyze. They discovered that women are more prone than men to the kind of excessive worry, apprehension, and fear that can prove disruptive in day-to-day living. Another finding: pregnant women, in particular, were at a higher risk for obsessive compulsive disorder (OCD)—a form of anxiety disorder—both during and immediately after pregnancy. 

More research is needed before the team can draw any definitive conclusions about why women are more likely to experience anxiety, but co-author Oliva Remes told the BBC that hormonal changes and the pressure of caring for children could be possible contributors.

Forbes points out that according to the World Health Organization, women are also twice as likely to suffer from depression as men, which could potentially predispose them to other nervous disorders. Compounding factors also include income inequality and post-traumatic stress after assaults. 

And gender wasn't the only thing that factors into who experiences anxiety, according to the researchers. They also found that anxiety disorders are more common for residents of North America and Western Europe than for those who live in other parts of the world. (North America tops the list with nearly 8 percent of people suffering from anxiety.) And age is a factor as well: Globally, as many as 10 percent of men and women under 35 had an anxiety disorder.

The WHO reports that just two out of five people who could benefit from mental health treatment seek help within a year of onset. Those in need of counseling can ask their physician for a referral or search for a provider with the Anxiety and Depression Association of America.

[h/t NY Mag]