Heavy drinking increases the risk of being injured, and far more so for women than men, researchers say.

In a review of emergency department admissions in 18 countries, they also found that violence was involved in twice as many drinking-related injuries as were traffic collisions, falls or other causes.

“Even small amounts of drinking put one at risk for injury,” said lead researcher Cheryl Cherpitel of the Alcohol Research Group in Emeryville, California.

After three standard drinks, both men and women were about 4.5 times more likely to be injured than when they were not drinking, the authors report in the journal Addiction.

But after that point, women’s risk started rising faster until it was double, then triple that of men. Compared to when they were not drinking, after 15 drinks men were 12 times more likely to be injured but women were 22 times more likely to be injured. The odds of injury peaked for both sexes at about 30 drinks.

A standard “drink” is typically any amount that contains 14 grams of pure alcohol. That would translate to 12 ounces of beer containing 5 percent alcohol, five ounces of wine with 12 percent alcohol or 1.5 ounces of hard liquor containing 40 percent alcohol.

The study looked at data on 13,119 injured men and women ages 18 and older who were admitted to 37 emergency departments after having up to 30 drinks in the previous six hours.

Those data included information from eight countries (Argentina, Belarus, Brazil, the Czech Republic, India, Mexico, New Zealand and Sweden) from a 2001-2002 World Health Organization study. The authors also added 2006-2009 data from 10 countries (Switzerland, Ireland, China and Korea, Dominican Republic, Guatemala, Guyana, Nicaragua, Panama and Canada) to get a better sense of the risks by gender, age, cause of injury and country-level drinking pattern.

Cherpitel, who also directs the WHO Collaborating Center on Alcohol Epidemiology and Injury, and her colleagues found that drinking-related injuries were more common in some countries, including Guatemala, Mexico and Nicaragua.

The researchers say injuries are a bigger problem in countries where regular moderate drinking, such as with meals, is less of a norm, so more drinking episodes are likely to be binge-drinking.

“People in the different countries can actually consume the same amount of alcohol but the pattern of drinking really makes a big difference,” said Cherpitel, noting that people in Mediterranean countries may drink a lot but spread it over a longer period of time.

They did not find any significant differences in drinking-related injuries by age group.

The differences between the sexes in injury risk may be due in part to men’s greater tolerance for alcohol, Cherpitel said.

Women were probably more likely to have violence-related injuries than men, judging from the study results, she noted. The study didn’t compare men and women’s risk of violence, but injuries involving altercations were twice as likely as traffic accidents and nearly twice as likely as falls.

“Certainly there are probably a lot of women who have not been drinking who are the victim of a violent episode because of who they were with,” Cherpitel said.

Dr. Maria Raven, an assistant professor of Emergency Medicine at the University of California, San Francisco, said that she and her colleagues routinely look for injuries whenever an intoxicated person comes to the emergency department.

“Maintaining that high index of suspicion is the safest way we have to assure we’re not missing significant injuries in people who are intoxicated,” Raven told Reuters Health. “All of us have found severe injury when we didn’t suspect we would.”