ANN ARBOR (WWJ) – A new University of Michigan study suggests women with post-traumatic stress disorder (PTSD) are likely to have smaller babies and deliver prematurely.

The research, Published in BJOG: An International Journal of Obstetrics and Gynaecology, found that mothers with PTSD who suffered abuse during childhood give birth to babies of lower-average weight and experience shorter gestation.

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PTSD is prevalent among women and can occur following traumatic events such as war, disaster, childhood maltreatment, rape and battering. Women with low income and education tend to have higher rates of PTSD in pregnancy, as do African American women.

U-M researchers looked at 839 women, of whom 41 percent were African American, from August 2005 to March 2008.

Children born to women with PTSD weighed a half pound less than traumatized women who did not develop PTSD, and nearly a half pound less than women who were not exposed to trauma. Among childhood abuse survivors, the association of current PTSD with lower birth weight was stronger.

The research also looked at race as a risk factor for PTSD. African American women are at no greater risk for onset of PTSD, but they are four times more likely to remain affected by the disorder at the time of pregnancy.

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“Preterm birth can cause serious health problems for babies,” said Julia Seng, a research associate professor at the U-M Institute for Research on Women and Gender and an associate professor of nursing. “An African American infant in Michigan is 70 percent more likely to be born prematurely than an infant of any other race. Therefore, PTSD, which affects African Americans more widely, may be an additional explanation for adverse perinatal outcomes, and it is a problem that is treatable.”

African Americans have more PTSD in pregnancy because they tend to receive less treatment and have more lifetime trauma exposures that may maintain or reactivate PTSD, Seng says. In addition, their average age at pregnancy is younger, which means less time between any abuse and pregnancy.

“It is essential that outcomes are improved in this high risk group of women. Maternity care needs to take traumatic stress into account with awareness being raised among health workers,” Seng said.

The study’s respondents were assigned to one of three follow-up cohorts after telephone interviews: women who were not exposed to trauma, women exposed to trauma but who did not suffer from PTSD, and women who had PTSD. The sample was also divided into groups with and without child abuse history in order to consider its impact.

The PTSD-affected cohort had more childhood abuse, substance use and recent intimate partner violence. They also had a lower rate of adequate prenatal care than the other women. The trauma-exposed resilient group had the fewest income and educational disadvantages and the highest rate of using adequate prenatal care.

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The researchers say that abuse-related PTSD may explain some of the adverse perinatal outcomes, especially those associated with low income and education and African American race in the United States. They add that screening for childhood abuse, PTSD and depression should occur at the start of prenatal care.