Women who suffer from depression before pregnancy should be monitored for manic symptoms—traits of bipolar disorder—during the postpartum period, according to new research published in the journal Bipolar Disorders.

Although women’s reproductive events (pregnancy, the postpartum period and menopause) are often linked to mood disorders, childbirth is more dramatic, explained Dr. Verinder Sharma, a psychiatrist from the Schulich School of Medicine & Dentistry at Western University in Canada.

“We know childbirth is a potent and specific trigger for mania and hypomania. What I wanted to do was to see, if you have a group of women with just depression, how many of them would convert to bipolar disorder after giving birth,” Sharma said. “A large number of women do convert.”

The study found that the occurrence of conversion from depression to bipolar disorder in postpartum women was 11-18 times higher than reported in non-postpartum women.

“If you look at the literature on postpartum mental illness, there’s lots of emphasis on postpartum depression; not much attention is paid to bipolar disorder,” Sharma said.

He also said that bipolar disorder in postpartum women tends to go unnoticed after a woman gives birth.

“When physicians and other caregivers are assessing women with postpartum depression, they have to screen them for bipolar disorder. This has important treatment implications and there are some safety issues as well. Bipolar disorder is more likely associated with suicide, and, perhaps, infanticide,” Sharma said.

He noted the importance of getting a diagnosis as soon as possible to ensure prompt and proper treatment, before symptoms escalate. Prescribing antidepressants to a woman whose diagnosis has converted to bipolar disorder wouldn’t be effective and could increase symptoms of mania, Sharma explained.

“If you look at women who get hospitalized for psychiatric reasons within the first couple of weeks after childbirth, a large number of them have bipolar disorder,” he said.

“We know childbirth is perhaps the most important and most potent trigger of bipolar disorder. We need to understand why that is the case, what is so unique about childbirth that it’s associated with such high risk,” he continued.

It is possible that genes, a family history of bipolar disorder, hormonal changes and sleep loss following pregnancy, contribute to the high risk. The researchers will continue to look into these factors to gain a better understanding of the underlying cause of the increased conversion of depression to bipolar disorder in postpartum women.

“For us to understand bipolar disorder in women, we have really neglected the role of hormonal changes,” he said.

“We now want to look at women who have just postpartum depression, to see whether the presence of manic symptoms (changes) in response to treatment.”

Source: University of Western Ontario

Mother holding her infant photo by shutterstock.