Previous breastfeeding practices and duration of exclusive breastfeeding in the United States.

We examined the influence of duration of exclusive breastfeeding (DEBF) for a mother's earlier children on the DEBF for her later children among multiparous women from the 2002 National Survey of Family Growth. DEBF was categorized as: never breastfed (NBF) (referent); not exclusively breastfed or exclusively breastfed for <4 months (EBF<4); and exclusively breastfed for ≥4 months (EBF≥4). We examined DEBF using weighted percentages and odds ratios (OR) with 95% confidence intervals (CI) from multinomial logistic regression models, adjusting for maternal factors. About 70% of multiparous women (n=2,149) repeated the duration of exclusive breastfeeding of their first child for their second child; 14% of women repeated EBF≥4. Among multiparous women, the adjusted odds ratio for EBF≥4 for second children was 7.2 (95% CI=4.0-12.9) when first children were EBF<4 and 90.7 (95% CI=45.4-181.4) when first children were EBF≥4, relative to NBF first children. In analyses where DEBF of third children was the outcome, odds of EBF≥4 were more strongly influenced by DEBF of second children while the impact of DEBF of first children was not as strong. Older maternal age and being married were related to an increased DEBF. Being married at second birth predicted a change from NBF for first children to EBF≥4 for second children (OR=6.2, 95% CI=2.7-14.2). In conclusion, mothers generally repeated the DEBF of their previous child. For third children, DEBF of the second child was more likely to be repeated than that of the first child.