The relationship between pregnancy wantedness and adverse pregnancy outcomes was studied using data from 2,828 mothers who participated in the Missouri Maternal and Infant Health Survey. The wantedness of a pregnancy was measured using traditional classifications of mistimed and unwanted, as well as additional measures gauging how the woman felt about the pregnancy while she was pregnant. Fifty-eight percent of the very low birth weight infants and 59% of the moderately low birth weight infants resulted from unintended pregnancies, as did 62% of the normal-birth-weight infants. Logistic regression showed that mothers of very low birth weight infants were significantly more likely than those who had a normal-weight baby to report that they had felt unhappy about the pregnancy (odds ratio of 1.53). Very low birth weight was also associated with early denial of the pregnancy (1.54). Odds ratios associating these two unwantedness categories with low-birth-weight babies were higher among Medicaid recipients than among women not receiving Medicaid. Associations between very low birth weight and the denial variable were also significant among white women when very low birth weight outcomes were compared with normal outcomes, but there was no significant association among black women. There were no significant associations between low birth weight and the traditional unwantedness variables.
(Family Planning Perspectives, 29:76-81, 1997)