Cognitive behavioral therapy can reduce tobacco smoke exposure among pregnant African-American women and subsequently improve birth outcomes, researchers have found.
Significantly fewer women who received the intervention delivered very preterm compared with controls (10% versus 48.8%, P=0.02). The same applied to infants with extremely low birth weight (19.1% versus 49.5%, P=0.01), according to Ayman A.E. El-Mohandes, MD, MPH, of the University of Nebraska Medical Center in Omaha, and colleagues.
The results are the first to show that "a cognitive-behavioral intervention that is delivered during prenatal care can assist black mothers in reducing their risk for environmental smoke exposure and improving their pregnancy outcomes," the researchers reported online in Pediatrics.
Smoking and secondhand smoke have long been associated with adverse pregnancy outcomes, particularly among black women, who may have increased exposure to secondhand smoke, the researchers said.
To test the efficacy of a cognitive behavioral therapy intervention, they studied 691 pregnant women in Washington from 2001 to 2004 in a randomized, controlled trial.
Each woman in the intervention group had a tailored counseling session adapted from evidence-based interventions for smoking reduction, focused on strategies within the home to eliminate or minimize exposure to tobacco smoke.
The control group received routine prenatal care.
In the study, the researchers saw that three times as many women reported environmental smoke exposure as reported smoking.
"Lower rates of smoking in pregnancy in black women should not be misinterpreted as an overall low risk for exposure to tobacco smoke," the researchers cautioned.
They found that women in the intervention group were significantly less likely to report smoke exposure before delivery (OR 0.50, 95% CI 0.35 to 0.71), but noted that Medicaid recipients were generally more likely to have smoke exposure than non-Medicaid patients (OR 1.97, 95% CI 1.31 to 2.96).
Also, smoking exposure decreased with advancing maternal age (OR 0.96, 95% CI 0.93 to 0.99).
Overall rates of very low birth weight and very preterm birth were significantly improved with the intervention as well (OR 0.11, 95% CI 0.01 to 0.86 and OR 0.22, 95% CI 0.07 to 0.68, respectively).
The researchers noted that mothers with highest levels of reproductive morbidity -- low birth weight and preterm birth -- had the highest rates of psychosocial and behavioral risk.
That may mean that such mothers may have benefited significantly from the cognitive behavioral therapy, which addressed multiple risk factors.
They added that the study was limited in its generalizability because it focused solely on black mothers, and may also have been limited by self-report.
The study was supported by grants from the Eunice Kennedy Shriver National Institute of Child Health and Human Development and the National Center of Minority Health and Health Disparities.
The authors have indicated they have no financial relationships relevant to this article.
Zalman S. Agus, MD Emeritus Professor
University of Pennsylvania School of Medicine and Dorothy Caputo, MA, RN, BC-ADM, CDE, Nurse Planner