Depression Common Before, During, and After Pregnancy

OAKLAND, Calif., Sept. 28 -- About one in seven women were depressed before, during, or after childbirth, according to a study of more than 4,300 women enrolled in the Kaiser Permanente HMO.

During the nine months before pregnancy, 8.7% of the women were diagnosed with depression, versus 6.7% of women who were treated for depression during pregnancy, and 10.4%, who had postpartum depression, said Evelyn Whitlock, M.D., M.P.H., of Kaiser Permanente Center for Health Research, a co-author of the study in the October issue of the American Journal of Psychiatry.

Overall, 678 women (15.4% of the sample) had depression diagnosed before, during, or after pregnancy, but the investigators said the differences in the rate of depression among the three periods were statistically significant (P <0.05).

And 54.2% of the women who were diagnosed with postpartum depression, had depression diagnoses before or during pregnancy.

Overall, 93.4% of the women who were diagnosed received treatment for their depression.

"The acceptability of treatment does support routing screening for depression, which could uncover undetected depression and, with appropriate treatment, mitigate the devastating effects of this disease on the mother, infant, and other siblings," the authors concluded.

Dr. Whitlock said that the observed rate of depression in this analysis was comparable to the "background, lifetime depression rate among women."

But the findings were useful because clinicians and the general public share a belief that while women are planning for a pregnancy and during a pregnancy, "women are unlikely to be depressed, at the same time, there is increased attention to depression during the postpartum period."

The investigators identified 4,398 women who had a least one pregnancy from Dec. 1, 1998 through Dec. 31, 2001. All women were continuously enrolled in the health plan for at least 39 weeks before the pregnancy and at least nine months after giving birth. Depression was identified by either ICD-9 code in the medical record or by an antidepressant dispensed within 30 days of a diagnosis of mental disorders

Seventy-nine percent of the women were white, 73% were age 20 to 34, 53% had completed at least 13 years education, and 76% were married.

Among the women diagnosed with depression at any time period studied, 17.5% also had a diagnosis of anxiety.

Only 13% of the women had their depression diagnosed by obstetrician-gynecologists, 41.3% were diagnosed by primary care physicians, and 30.7% had depression diagnosed by a mental health provider.

Depression was most often diagnosed in women who had three or more children before the index pregnancy, women who smoked during pregnancy, or who were Medicaid patients.

Age, education, and trimester of entry into a prenatal care program were not associated with depression.

Seventy-seven percent of the women diagnosed with depression before pregnancy filled at least one prescription for an antidepressant, as did 67% of the women diagnosed during pregnancy, and 82% diagnosed postpartum.

Selective serotonin reuptake inhibitors (SSRIs) were the most commonly prescribed antidepressant and 180 women received them during pregnancy. The authors noted that the time period studied predated information about a possible link between maternal SSRI use and persistent pulmonary hypertension or cardiovascular malformations in newborns. (See: No Link Found Between SSRIs and Congenital Heart Disease)

Kimberly A. Yonkers, M.D., of Yale wrote in an editorial that although the database used in the study provided a large sample size, it did not supply precise information about possible confounders "such as health habits and illness characteristics."

Moreover, although depression was more common in the postpartum period, more than 50% of the women who were diagnosed with a depressive disorder after delivery were also diagnosed with a depressive disorder before delivery.

And, Dr. Yonkers wrote that it was not clear whether the increase in diagnoses after delivery was a "result of patients' willingness to disclose depressive symptoms after delivery, clinicians' increased vigilance in diagnosing depression disorders postnatally, or a true difference in the incidence of depression."