A randomized trial of an empirically-derived social support intervention to prevent low birthweight among African American women.

Previous clinical trials of social support interventions to reduce low birthweight (LBW) have not fully capitalized on findings from social science research, and therefore have not used empirically-derived criteria to define a low social support population or to develop the intervention. To overcome limitations of previous studies, this randomized clinical trial tested the hypothesis that an empirically-derived social support intervention would reduce LBW among African American women. Based on prior work, African American women were identified as at-risk for LBW due to inadequate social support if they lacked support from their mothers or male partners. Focus groups were used in this study to develop a culturally-relevant intervention. Adult low-income African American pregnant women (n = 319) were tested for inadequate social support in mid-pregnancy. Of these, 114 (36%) low-support women were identified and randomly assigned to the intervention group (n = 56) or control group (n = 58). The intervention was designed to provide the support usually provided by the pregnant woman's mother or male partner. It consisted of four standardized face-to-face sessions at two week intervals and telephone contact in the intervening weeks. Birthweight was obtained blinded from charts or birth certificates, with 99% follow-up. The rate of LBW (below 2500 grams) was 9.1% in the intervention group compared to 22.4% in the control group (P < 0.05). Contrary to previous studies, this social support intervention was effective in reducing the rate of LBW. It is promising that this intervention was successful for African Americans because the rate of LBW is twice as high among African Americans than among Caucasians.