The study, published in the current issue of Archives of Women's Mental Health, suggests that recent exposure to intimate partner violence, or IPV, is a much stronger prenatal predictor of postpartum depression than even prenatal depression, which is generally considered the most significant predictor.
In addition, recent partner violence has a stronger effect on postpartum depression than prior episodes of trauma from either partners or non-partners, the researchers said.
The authors suggest that pregnant women be screened for both prenatal depression and IPV.
"The study brings attention to the role that partner violence plays in postpartum depression and is particularly unique in that it examines this problem in an understudied but high-risk population of pregnant and postpartum Latinas in Los Angeles," said lead study author Jeanette M. Valentine, a visiting associate researcher at the Center for Health Services and Society at the Semel Institute for Neuroscience and Human Behavior at UCLA.
"It stresses the importance of prenatal screening for not only postpartum depression but partner violence as well, with such screening potentially contributing to interventions that could prevent the onset of postnatal depression and its adverse consequences for mother, infant and family."
This research derives from Proyecto Cuna (Baby Cradle), a study begun in 2003 to trace the effects of trauma on maternal and child health among Latinas. Participants were recruited from obstetric and gynecologic clinics at two private, nonprofit health care organizations in largely Latino communities. In total, 210 women, aged 18 and older, were enrolled in the current study.
The researchers found that women who had experienced IPV during pregnancy or within the 12 months prior to pregnancy were 5.4 times more likely to suffer postpartum depression than women who had not experienced recent IPV.
"This finding is true even after controlling for prenatal depression and low social support, which shows that recent IPV exposure during and close to the pregnancy is a very strong predictor of postpartum depression among Latinas," Valentine said.
The study also found that women who had experienced prenatal depression were 3.5 times likelier to experience postpartum depression than women who had not experienced prenatal depression.
Among the other findings:
• 43.7 percent of the women (83 participants) met the criteria for depression during their first postpartum year.
• 33.2 percent (63) demonstrated depression symptoms during the prenatal period.
• 20.5 percent (39) experienced IPV within the prior 12 months.
• 23.2 percent (44) had experienced IPV further in the past.
According to the authors, the study does have some limitations, given that the subjects were largely Spanish-speaking, non-U.S. born, low-income Latinas, and the results may not be entirely applicable to other populations. Still, they said, the findings merit further study.
The next step, according to Valentine, will be to "examine the impact of intimate partner violence on the behavioral and emotional well-being of the offspring and IPV's possible interaction with maternal depression in adversely affecting children's mental health."
"This research has significant implications for the prevention of and early intervention in children's mental health conditions," she said.
A grant from the National Institute of Mental Health to the UCLA Center for Trauma, Culture and Mental Health Disparities funded this study.
Valentine's co-authors on the study are Michael Rodriguez and Muyu Zhang of UCLA, and Lisa M. Lapeyrouse of the University of Texas–El Paso.
The UCLA Center for Culture, Trauma and Mental Health Disparities is a unique interdisciplinary center that promotes research into the behavioral, biological, psychological and social factors associated with trauma among ethnic minorities with the aim of understanding how depression, post-traumatic stress disorder and other mental health outcomes affect men and women who may not seek or receive effective care. This understanding can help health care professionals create new strategies to reduce mental health disparities among these groups.