New research suggests the class of antidepressants called selective serotonin reuptake inhibitors (SSRIs), which are generally used to treat symptoms associated with menopause, could raise women's risk of bone fractures.

This heightened risk is believed to persist for several years following the treatment, suggesting shorter therapy length may be safer, the British Medical Journal (BMJ) reported. SSRIs are the third most frequently prescribed class of drugs in the U.S., and are often used to treat menopause-related symptoms such as irritable bowel syndrome, night sweats, and hot flashed.

To make their findings, a team of researchers looked at 137,031 women between the ages of 40 and 64 with no mental health issues. These women were prescribed SSRIs including "citalopram, hyrdrobromide, escitalopram oxalate, fluoxetine hyrdrochloride, fluvoxamine maleate, paroxetine hydrochloride and sertraline hydrochloride." The sample was compared with a control group made up of more than 236,294 women of the same age who were instead prescribed H2 antagonists or proton pump inhibitors (PPIs) to treat indigestion.

An analysis of the data concluded fracture rates were significantly higher among women treated with SSRIs. The fracture rate was found to be 76 percent higher among those who were prescribed SSRIs one year after starting treatment, and 73 percent higher after two years; after five years the fracture rate was 67 percent higher than those treated with indigestion drugs.

Although the study is observational, and cannot form a definitive conclusion, the findings suggest antidepressants could alter bone turnover and lead to bone thinning.

"SSRIs appear to increase fracture risk among middle aged women without psychiatric disorders, an effect sustained over time, suggesting that shorter duration of treatment may decrease [this]," the researchers concluded. "Future efforts should examine whether this association pertains at lower doses."

The findings were published in a recent edition of the journal Injury Prevention.