PREVENTION OF INTELLECTUAL IMPAIRMENT IN CHILDREN OF WOMEN WHO SMOKE CIGARETTES DURING PREGNANCY

Objective. To analyze the influence of a comprehensive program of nurs e home visitation on the intellectual functioning of children born to women who smoked cigarettes during pregnancy. Design. Randomized clini cal trial. Treatment 1: sensory and developmental screening at ages 1 and 2 years; treatment 2: screening plus free transportation for prena tal and well-child care; treatment 3: screening, transportation, plus prenatal home visitation; treatment 4: screening, transportation, pren atal home visitation, plus postnatal home visitation through the child ren's second birthdays. Setting. Semirural community in Upstate New Yo rk. Participants. 400 families in which the mothers registered before the 30th week of pregnancy and had no previous live births. Eighty-fiv e percent of the mothers were either teenagers, unmarried, or poor. An alysis was limited to whites, who constituted 89% of sample. Intervent ion. Nurse home visitation during pregnancy (treatments 3 and 4) or du ring pregnancy and the first 2 years of the child's life (treatment 4) . During pregnancy, the nurses helped women improve their health-relat ed behaviors, informal social support, and linkage with needed communi ty services. Main findings. Children born to women who smoked 10 or mo re cigarettes per day at registration during pregnancy and who were as signed to treatments 3 and 4 had IQs (averaging across the 3rd and 4th years of life) that were 4.86 (95% CI: 0.47, 9.26) points higher afte r adjustment for covariates than did children born to women who smoked 10+ cigarettes per day and who were assigned to treatments 1 and 2. T he positive influence of the home-visiting program on reducing the har mful effect of smoking appears to be due to prenatal visitation. Concl usion. Comprehensive prenatal home-visitation services can offset the impairment in intellectual functioning associated with substantial mat ernal smoking during pregnancy.