Women who suffer from major depression have some tough choices to make when they become pregnant.
New research released this week won't necessarily make those decisions any easier.
Doctors used to think it was possible to stop taking antidepressants during pregnancy because the surge of hormones would help keep depression at bay.
But the research suggests this isn't the case. A study of 201 pregnant women with a history of depression compared a group of patients who went off their medications to others who didn't.
Of those who stopped the drugs, 68 per cent fell back into depression, indicating natural hormones didn't provide a buffer.
Of those who kept taking their medication, only 26 per cent became depressed.
The findings, published in the Journal of the American Medical Association, outline the dilemma for these women.
Studies indicate that some antidepressant medications could pose a risk to a fetus.
But depression during pregnancy can also be bad, because maternal mood disorders can affect the fetus.
The researchers, led by Lee Cohen of Massachusetts General Hospital, suggest that women talk to the doctors about the pros and cons of treatment.