Abstract: A prospective survey of maternal employment and breast-feeding initiation and duration was conducted among 668 Black and 511 White women who delivered their first child in Washington, DC. Ninety-one percent of White women (n = 511) and 80 percent of Black women (n = 668) reported working during pregnancy. Black women who planned to return to work part time vs full time were more likely to breast-feed rather than formula-feed (adjusted odds ratio, 2.3; 95% confidence intervals (CI) = 1.4, 3.7). Using Cox regression, Black women who returned to work had a shorter duration of breast-feeding than those not returning to work (hazard ratio = 0.5 (CI = 0.3, 0.9)). Black and White women returning to professional occupations had a longer duration of breast-feeding compared to women returning to sales or technical positions (hazard ratio for Black women = 2.4 (CI = 1.4, 4.4); hazard ratio for White women = 1.6 (CI = 1.0, 2.5)). In addition, White women in professional occupations had a longer duration of breastfeeding than women in clerical positions (hazard ratio = 1.7 (CI = 1.1, 2.6)). Until employers in the United States develop a maternity policy which does not discourage breast-feeding, the recommended six months of breast-feeding will be difficult to achieve for most employed women. (Am J Public Health 1989; 79:1247-1250). [ABSTRACT FROM AUTHOR]