A study published in the Annals of Internal Medicine found the suicide rate among women physicians was 130 percent higher than among the general population and among male doctors it was 40 percent higher.

A survey of 4,287 students at seven medical schools revealed that many U.S. medical students think about suicide, suggesting that physicians' increased risk for suicide may begin in medical school.

The study said both personal distress and professional distress, or "burnout," were linked to thinking about suicide.

While the relationship between depression and suicide is well-recognized, the association between burnout and thinking about suicide has not been previously reported, the researchers said. Burnout is common among medical students, and is associated with a two- to three-fold increased risk of thinking about suicide.

In the study, 26 percent of burned out students recovered within the following year, indicating that burnout is reversible, the study said.