NEW YORK (Reuters Health) – For pregnant women diagnosed with major depressive disorder, treatment with omega-3 fatty acid supplements may reduce depressive symptoms, according to the findings of a small clinical trial.

“Perinatal depression is common, and treatment remains challenging,” Dr. Kuan-Pin Su, of China Medical University Hospital, Taiwan, and colleagues explain in the Journal of Clinical Psychiatry.

When a pregnant woman needs to be treated for major depression, “the possible risks and benefits of antidepressant medication are considered to have significant impacts on both mother and baby,” Su commented to Reuters Health. “Many women and their health care providers prefer the use of non-medication treatments,” Su added.

“Depression has been reported to be associated with the abnormality of omega-3 polyunsaturated fatty acids (PUFAs),” the team notes in their article. They propose that the requirements of the growing baby lead to “a profound decrease of omega-3 PUFAs in the mother during pregnancy,” and this might “precipitate the occurrence of depression.”

To see if omega-3 supplements would help, the researchers assigned 36 pregnant women with depression to take 3.4 grams of omega-3 PUFAs or an inactive placebo daily for eight weeks.

No antidepressants or other mood-altering drugs were given for one month before the study began or during the study. A total of 24 women completed the study — 13 in the treatment group and 11 in the placebo group.

Patients given omega-3 PUFAs had significantly lower scores on a standardized depression scale after 6 and 8 weeks compared with those who received placebo. Furthermore, depression improved significantly in 62 percent of the women in the omega-3 group compared with 27 percent of those in the placebo group

The omega-3 supplements were well tolerated. Adverse events related to treatment included insomnia, nausea and diarrhea, but no pregnancy complications were reported, and there were no adverse effects on the newborns.

However, Su cautioned that before omega-3 fatty acids can be considered as a primary treatment for depression in pregnant women, the results need to be replicated in larger studies. Furthermore, the researcher added, the optimal dosage and type of omega-3 PUFAs “need to be determined for this specific population.”

SOURCE: Journal of Clinical Psychiatry, April 2008.