SAN DIEGO — Results from the first population-based study of its kind have found that about one in three mothers of inconsolable, crying infants reported having postpartum depressive symptoms, Pamela C. High, M.D., said at the annual meeting of the Society for Developmental and Behavioral Pediatrics.
Dr. High and her associates analyzed data from Rhode Island's Pregnancy Risk Assessment Monitoring System (PRAMS) that was weighted to represent all births that occurred in the state in 2002 and 2003. Sponsored by the Centers for Disease Control and Prevention, PRAMS is an ongoing state-specific population-based survey that identifies and monitors selected maternal behaviors and experiences before, during, and after pregnancy. Rhode Island is one of 32 states that has the system.
The investigators mailed a survey to 4,214 mothers that included a question about their infants' consolability as well as a question about maternal depressive symptoms, said Dr. High, director of developmental and behavioral pediatrics at Rhode Island Hospital/Hasbro Children's Hospital, Providence.
Of the 4,214 mothers, 2,947 returned questionnaires, for a response rate of 70%.
Nearly 10% of respondents were in their teens, almost half in their 20s and an additional 27% were aged 30–34 years. The majority of them (87%) were white, while 8% were black. The rest were of Hispanic, Asian, or American Indian background.
The mean infant age was 16 weeks and nearly half were males.
Overall, mothers identified 8.3% of the infants as being “somewhat difficult” or “very difficult” to console. Infants who weighed less than 2,500 g at birth were reported to be more difficult to console compared with heavier newborns (11.2% vs. 8.1%, respectively).
Among the respondents, 7.7% of whites, 9.4% of blacks, and 17.1% of those from other racial backgrounds said they had infants who were difficult to console.
No significant differences were seen with maternal age, Hispanic ethnicity, maternal education, marital status, household income, parity, or breast-feeding.
In the assessment, 19.2% of mothers reported that in the months after delivery, they felt “moderately depressed,” “very depressed,” or “very depressed and had to get help.”
Higher levels of postpartum depression were reported by mothers who had not completed high school or who only had a high school education. Other risk factors included being unmarried, having an annual household income of less than $40,000, and being on public health insurance.
Mothers of infants who weighed less than 2,500 g at birth reported more depression than did those with heavier newborns (29.2% vs. 18.4%), while mothers with unintended pregnancies reported more depression than did those with planned pregnancies (22.8% vs. 16.8%).
Maternal age, race, ethnicity, and parity did not predict depression in these mothers. Slightly more than one-third of mothers with inconsolable infants (34.7%) also reported postpartum depressive symptoms, compared with 17.4% of mothers with infants described as more easily consoled. Physicians, then, should consider screening for postpartum depression when a new mother comes in with an inconsolable infant, the researchers suggested.
Logistic regression analysis, adjusted for socioeconomic factors, revealed that mothers with postpartum depressive symptoms were 2.59 times more likely to report infant inconsolability than were mothers who did not report postpartum depressive symptoms.
Dr. High called the association between maternal depression and infant inconsolability “robust,” but noted that a limitation of the study includes the fact that infant inconsolability and maternal depression were measured by a single question. “Also, the population sampled is not necessarily representative of the rest of the United States,” she said.