Racial and Ethnic Differences in Breastfeeding Initiation and Duration, by State --- National Immunization Survey, United States, 2004--2008

Racial and Ethnic Differences in Breastfeeding Initiation and Duration, by State --- National Immunization Survey, United States, 2004--2008
Weekly
March 26, 2010 / 59(11);327-334

The American Academy of Pediatrics recommends exclusive breastfeeding to age 6 months and continued breastfeeding for at least the first year of life (1). The Healthy People 2010 (HP2010) targets (16-19a--c) for initiating breastfeeding, breastfeeding to age 6 months, and breastfeeding to age 12 months, are 75%, 50%, and 25%, respectively. National estimates from the United States indicate substantial racial/ethnic differences in breastfeeding (2). To monitor state-specific progress toward achieving the HP2010 objectives for breastfeeding initiation and duration among different racial/ethnic groups, CDC analyzed 2004--2008 National Immunization Survey (NIS) data for children born during 2003--2006. This report summarizes the results of that analysis, which found that non-Hispanic blacks had a lower prevalence of breastfeeding initiation than non-Hispanic whites in all but two states; Hispanics generally had lower prevalence than non-Hispanic whites in western states and higher in eastern states. Most states were not meeting the HP2010 targets for breastfeeding duration for any racial/ethnic group. Breastfeeding should be promoted through comprehensive clinical and social supports starting in pregnancy, and including the birth, delivery, and postpartum periods.

NIS is an ongoing, random-digit--dialed survey in 50 states and the District of Columbia that includes households with children aged 19--35 months at the time of interview (3). Although the survey primarily is intended to estimate national, state, and selected urban area vaccination coverage rates, questions on breastfeeding initiation and duration were added to NIS in 1999. Because children are aged 19--35 months at the time of the NIS interview, each cross-sectional survey includes children born in 3 different calendar years. To maximize sample size and allow for representative state-level analyses stratified by racial/ethnic group, data from the 2004--2008 surveys were combined to create a cohort of children born during 2003--2006. Council of American Survey Research Organizations (CASRO) response rates for NIS 2004--2008 ranged from 63% to 72%.* The child's race/ethnicity, and mother's age, education, and participation in the Women, Infants, and Children (WIC) supplemental nutrition program were self-reported. Data were suppressed when sample size was <50 because of unstable estimates. Because of inadequate sample sizes for other racial/ethnic groups, analyses by state were restricted to children whose racial/ethnic groups were categorized as Hispanic, non-Hispanic white, or non-Hispanic black. Data were weighted to adjust for households with multiple telephone lines, household nonresponse, and exclusion of households without landline telephones. Estimates were adjusted using final survey weights to correct for nonresponse (3). T-tests were used to determine whether estimates for Hispanics and non-Hispanic blacks were significantly different (p<0.05) from estimates for non-Hispanic whites.

To assess breastfeeding initiation, survey participants were asked "Was [child] ever breastfed or fed breast milk?" To assess breastfeeding duration, in NIS 2004 and 2005, survey participants were asked "How long was [child] breastfed or fed breast milk?" The wording changed slightly for NIS 2006 onwards to "How old was [child's name] when [child's name] completely stopped breastfeeding or being fed breast milk?"; these changes had a minimal effect on estimates of breastfeeding duration.†

National estimates for breastfeeding initiation and duration to 6 months and 12 months were 73.4%, 41.7%, and 21.0%, respectively (Table 1). Breastfeeding estimates varied by race/ethnicity, participation in the WIC supplemental nutrition program, and mother's age and education.

In the state-specific analysis, for all but two states (Minnesota and Rhode Island), prevalence of breastfeeding initiation was lower among non-Hispanic blacks than non-Hispanic whites, although these differences were not significant in all such states (Table 2). In 13 states, the difference between non-Hispanic blacks and non-Hispanic whites was ≥20 percentage points, with the largest differences observed predominantly in southeastern states. In six states the prevalence of breastfeeding initiation among non-Hispanic blacks was less than 45%. In general, compared with non-Hispanic whites, lower prevalence of breastfeeding initiation was observed among Hispanics in western states and higher prevalence was observed among Hispanics in eastern states.

Among states with sample sizes sufficient for analysis (≥50 respondents per group), Hispanics, non-Hispanic whites, and non-Hispanic blacks met the HP2010 targets§ for breastfeeding initiation of 75% in 33 of 49, 27 of 51, and one of 33 states, respectively (Figure). For breastfeeding duration, Hispanics, non-Hispanic whites, and non-Hispanic blacks met the HP2010 targets of 50% breastfeeding to 6 months in eight of 49, 14 of 51, and two of 33 states, and of 25% breastfeeding to 12 months in 12 of 49, 14 of 51, and three of 33 states, respectively.

Reported by
KS Scanlon, PhD, L Grummer-Strawn, PhD, R Li, PhD, J Chen, MS, Div of Nutrition, Physical Activity and Obesity, National Center for Chronic Disease Prevention and Health Promotion; N Molinari, PhD, Immunization Svcs Div, National Center for Immunization and Respiratory Diseases; CG Perrine, PhD, EIS Officer, CDC.

open here to see the full-text:
http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5911a2.htm?s_cid=mm5911a2_e