Final Formula Supplementation of Breast Milk Rates by Socio-demographic Factors, Among Children Born in 2005 (Percent +/- half 95% Confidence Interval)
Socio-demographic Factors n Formula
Supplementation1
within first
2 days of life		 n Formula
Supplementation1
before 3 months
of age		 n Formula
Supplementation1
before 6 months
of age
US National 18114 24.9±1.1 14354 38.1±1.4 10901 44.9±1.7
Sex
  Male 9222 25.6±1.6 7260 38.8±2.0 5519 45.8±2.4
  Female 8892 24.1±1.6 7094 37.4±2.0 5382 43.9±2.3
Race/ethnicity
  American Indian or Alaska Native 572 18.6±5.2 465 36.3±9.8 346 46.6±11.5
  Asian or Pacific Islander 1329 30.0±4.4 1144 44.1±5.7 912 49.3±6.5
    -Asian 1120 30.4±4.8 977 44.4±6.2 785 49.1±7.2
    -Native Hawaiian and other 276 28.0±8.8 222 41.9±11.4 168 49.5±13.1
  Black or African American 2066 30.6±3.3 1555 46.1±4.0 1039 55.0±4.8
  White 15166 23.8±1.2 12023 36.8±1.5 9219 43.3±1.8
  Hispanic or Latino 3842 33.6±2.6 3026 43.8±3.1 2163 50.0±3.8
  Not Hispanic or Latino (NH) 14272 20.9±1.1 11328 35.4±1.4 8738 42.6±1.7
    -NH Black or African American 1743 29.3±3.4 1308 45.5±4.2 882 55.6±5.1
    -NH White 11783 18.7±1.2 9355 33.2±1.6 7305 40.5±1.8
Birth Order
  First Born 9340 23.8±1.6 7596 37.0±1.9 5840 44.4±2.3
  Not First Born 8774 26.0±1.6 6758 39.4±2.0 5061 45.4±2.4
Receiving WIC2
  Yes 6644 29.6±1.9 4817 42.6±2.5 3333 49.3±3.0
  No, but eligible 860 17.9±4.8 726 27.2±6.0 600 31.7±7.0
  Ineligible 9708 20.4±1.3 8045 35.1±1.7 6355 43.0±2.0
Maternal Age, Years
  <20 284 27.4±8.9 170 36.2±12.7 103 43.3±16.7
  20-29 5857 25.0±1.9 4289 38.1±2.5 3020 42.6±3.1
  >=30 11973 24.7±1.4 9895 38.1±1.7 7778 46.0±2.0
Maternal Education
  Not a High School Graduate 1810 36.4±3.6 1356 46.7±4.4 958 52.6±5.4
  High School Graduate 2808 23.6±2.4 2029 37.9±3.2 1426 40.8±3.8
  Some College 4859 22.9±2.0 3600 34.6±2.6 2584 40.9±3.2
  College Graduate 8637 20.9±1.4 7369 35.9±1.7 5933 45.6±2.0
Maternal Marital Status
  Married 14646 23.6±1.2 11982 36.7±1.5 9348 43.9±1.8
  Unmarried3 3468 28.6±2.5 2372 43.2±3.4 1553 49.0±4.2
Residence
  MSA4, Central City 7890 27.7±1.7 6336 40.4±2.2 4829 48.3±2.5
  MSA, Non-Central City 6889 24.4±1.8 5461 38.0±2.2 4134 43.8±2.6
  Non-MSA 3335 18.1±2.5 2557 31.1±3.2 1938 37.3±3.8
Poverty Income Ratio5,%
  <100% 2805 29.7±2.8 2079 40.4±3.6 1447 48.0±4.5
  100%-184% 2543 25.0±3.0 1921 38.9±4.1 1424 42.6±4.8
  185%-349% 4378 20.2±2.0 3487 35.0±2.5 2720 41.8±2.9
  ≥350% 6827 21.0±1.6 5631 35.9±2.1 4369 44.4±2.5

1Formula supplementation is defined as supplementation of breast milk with formula (with or without other supplementary liquids or solids) among infants breastfed at the age specified (48 hours, 3 months, or 6 months). The denominator for the 2 day, 3 month, or 6 month rate is the number of infants breastfeeding at 2 days, 3 months, or 6 months, respectively.
2WIC = Special Supplemental Nutrition Program for Women, Infants, and Children.
3Unmarried includes never married, widowed, separated, divorced.
4MSA = Metropolitan Statistical Area defined by the Census Bureau.
5Poverty Income Ratio = Ratio of self-reported family income to the federal poverty threshold value depending on the number of people in the household.

Source: National Immunization Survey, Centers for Disease Control and Prevention, Department of Health and Human Services

Sample sizes appearing in the NIS breastfeeding tables are slightly smaller than the numbers published in other NIS publications due to the fact that in the DNPAO breastfeeding analyses, the sample was limited to records with valid responses to the breastfeeding questions.