Table 2. Descriptive Statistics of Individual-Level Characteristics by Racial/Ethnic Group and Medicaid Expansion Status in the Pre–Medicaid Expansion Perioda.
| Overall (Births to Mothers of All Races/Ethnicities)b | Characteristics Stratified by Race/Ethnicity | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Non-Hispanic White | Non-Hispanic Black | Hispanic | ||||||||||
| %c | Difference (95% CI)c |
%c | Difference (95% CI)c |
%c | Difference (95% CI)c |
%c | Difference (95% CI)c |
|||||
| Expansion | Nonexpansion | Expansion | Nonexpansion | Expansion | Nonexpansion | Expansion | Nonexpansion | |||||
| No. of births | 4 396 572 | 3 355 553 | 2 301 966 | 1 835 476 | 553 056 | 539 803 | - | 1 118 300 | 816 119 | - | ||
| Maternal Characteristics | ||||||||||||
| Payment sourced | ||||||||||||
| Medicaid | 42.1 | 44.5 | −2.3 (−2.4 to −2.3) | 27.4 | 34.3 | −6.9 (−7.0 to −6.8) | 65.4 | 68.2 | −2.9 (−3.0 to −2.7) | 65.1 | 53.7 | 11.3 (11.2 to 11.5) |
| Private | 50.7 | 43.9 | 6.8 (6.7 to 6.9) | 65.3 | 57.9 | 7.4 (7.3 to 7.5) | 27.8 | 23.9 | 3.8 (3.7 to 4.0) | 28.0 | 23.4 | 4.6 (4.5 to 4.7) |
| Other | 4.6 | 5.5 | −0.9 (−1.0 to −0.9) | 4.8 | 4.3 | 0.5 (0.4 to 0.5) | 5.1 | 3.9 | 1.2 (1.1 to 1.2) | 4.0 | 9.1 | −5.2 (−5.3 to −5.1) |
| Self-paye | 2.6 | 6.2 | −3.6 (−3.6 to −3.5) | 2.5 | 3.5 | −1.0 (−1.0 to −1.0) | 1.8 | 3.9 | −2.1 (−2.2 to −2.1) | 3.0 | 13.7 | −10.8 (−10.8 to −10.7) |
| Race/ethnicityf | ||||||||||||
| Non-Hispanic whitee | 52.4 | 54.7 | −2.3 (−2.4 to −2.3) | |||||||||
| Non-Hispanic black | 12.6 | 16.1 | −3.5 (−3.6 to −3.5) | |||||||||
| Hispanic | 25.4 | 24.3 | 1.1 (1.1 to 1.2) | |||||||||
| Other | 9.6 | 4.9 | 4.7 (4.7 to 4.8) | |||||||||
| Age category, yg | ||||||||||||
| 18-21e | 15.7 | 19.7 | −4.1 (−4.1 to −4.0) | 12.4 | 16.5 | −4.1 (−4.2 to −4.0) | 25.1 | 28.4 | −3.3 (−3.5 to −3.1) | 21.1 | 22.8 | −1.7 (−1.8 to −1.6) |
| 22-25 | 20.6 | 23.5 | −2.9 (−3.0 to −2.9) | 19.4 | 23.0 | −3.7 (−3.8 to −3.6) | 24.8 | 26.1 | −1.3 (−1.4 to −1.1) | 23.4 | 24.0 | −0.6 (−0.7 to −0.4) |
| 26-30 | 31.1 | 30.5 | 0.7 (0.6 to 0.7) | 33.5 | 33.2 | 0.3 (0.2 to 0.4) | 25.8 | 24.7 | 1.1 (0.9 to 1.3) | 27.8 | 27.4 | 0.4 (0.3 to 0.6) |
| 31-35 | 22.9 | 19.0 | 3.9 (3.9 to 4.0) | 25.0 | 20.2 | 4.8 (4.7 to 4.9) | 16.5 | 14.6 | 1.9 (1.8 to 2.0) | 18.8 | 17.8 | 1.0 (0.9 to 1.1) |
| ≥36d | 9.7 | 7.3 | 2.4 (2.3 to 2.4) | 9.8 | 7.1 | 2.7 (2.6 to 2.7) | 7.8 | 6.2 | 1.6 (1.5 to 1.6) | 8.9 | 8.0 | 0.9 (0.8 to 1.0) |
| Educational status | ||||||||||||
| High school or lesse | 38.9 | 41.2 | −2.4 (−2.5 to −2.3) | 27.0 | 29.7 | −2.8 (−2.8 to −2.7) | 48.2 | 48.6 | −0.4 (−0.6 to −0.2) | 63.9 | 64.3 | −0.4 (−0.5 to −0.3) |
| Attended or completed college | 48.7 | 50.3 | −1.6 (−1.7 to −1.5) | 56.2 | 59.3 | −3.1 (−3.2 to −3.0) | 46.5 | 46.4 | 0.0 (−0.2 to 0.2) | 32.9 | 32.8 | 0.1 (−0.0 to 0.3) |
| More than bachelor’s | 12.5 | 8.5 | 4.0 (3.9 to 4.0) | 16.8 | 10.9 | 5.9 (5.8 to 6.0) | 5.4 | 5.0 | 0.4 (0.3 to 0.5) | 3.2 | 3.0 | 0.3 (0.2 to 0.3) |
| Body mass index categoryh | ||||||||||||
| Underweight | 3.6 | 3.8 | −0.2 (−0.2 to −0.2) | 3.5 | 4.1 | −0.6 (−0.6 to −0.6) | 3.2 | 3.4 | −0.2 (−0.2 to −0.1) | 2.4 | 2.8 | −0.4 (−0.4 to −0.3) |
| Normal weighte | 47.2 | 45.9 | 1.3 (1.2 to 1.3) | 51.2 | 49.7 | 1.5 (1.5 to 1.6) | 35.3 | 35.0 | 0.2 (0.0 to 0.4) | 39.3 | 42.4 | −3.1 (−3.2 to −3.0) |
| Overweight or obese | 49.2 | 50.3 | −1.1 (−1.1 to −1.0) | 45.3 | 46.3 | −0.9 (−1.0 to −0.8) | 61.5 | 61.6 | −0.1 (−0.2 to 0.1) | 58.2 | 54.8 | 3.5 (3.3 to 3.6) |
| Married | 61.9 | 61.4 | 0.5 (0.4 to 0.6) | 73.0 | 72.8 | 0.2 (0.1 to 0.3) | 29.6 | 30.6 | −1.0 (−1.2 to −0.8) | 47.9 | 52.8 | −4.9 (−5.0 to −4.7) |
| Previous preterm birth | 2.4 | 2.4 | −0.0 (−0.0 to 0.0) | 2.5 | 2.5 | −0.1 (−0.1 to −0.0) | 4.1 | 3.1 | 1.0 (0.9 to 1.1) | 1.9 | 1.9 | −0.0 (−0.0 to 0.0) |
| Prepregnancy diabetesi | 0.7 | 0.8 | −0.1 (−0.1 to −0.1) | 0.6 | 0.7 | −0.1 (−0.1 to −0.0) | 1.1 | 1.1 | −0.0 (−0.1 to 0.0) | 0.8 | 0.9 | −0.2 (−0.2 to −0.1) |
| Prepregnancy hypertensioni | 1.4 | 1.6 | −0.1 (−0.1 to −0.1) | 1.3 | 1.4 | −0.1 (−0.1 to −0.1) | 3.3 | 3.1 | 0.3 (0.2 to 0.3) | 0.8 | 0.9 | −0.1 (−0.1 to −0.1) |
| Pregnancy hypertensioni | 4.1 | 4.9 | −0.8 (−0.9 to −0.8) | 4.4 | 5.1 | −0.7 (−0.7 to −0.6) | 5.8 | 6.0 | −0.1 (−0.2 to −0.1) | 3.0 | 4.1 | −1.1 (−1.2 to −1.1) |
| Eclampsiai | 0.2 | 0.2 | 0.1 (0.1 to 0.1) | 0.2 | 0.2 | 0.1 (0.1 to 0.1) | 0.4 | 0.2 | 0.2 (0.1 to 0.2) | 0.2 | 0.1 | 0.1 (0.0 to 0.1) |
| Any infectioni | 2.0 | 2.6 | −0.5 (−0.5 to −0.5) | 1.4 | 1.6 | −0.2 (−0.2 to −0.2) | 5.2 | 5.9 | −0.7 (−0.8 to −0.6) | 1.5 | 2.4 | −0.9 (−0.9 to −0.8) |
| Infant Characteristics | ||||||||||||
| Prenatal care in first trimester | 77.6 | 71.9 | 5.7 (5.7 to 5.8) | 81.1 | 78.0 | 3.1 (3.1 to 3.2) | 66.6 | 63.9 | 2.7 (2.5 to 2.8) | 75.3 | 63.6 | 11.7 (11.6 to 11.8) |
| Total birth order | ||||||||||||
| 1e | 31.3 | 30.7 | 0.6 (0.5 to 0.7) | 33.7 | 33.2 | 0.5 (0.4 to 0.6) | 26.0 | 28.6 | −2.6 (−2.7 to −2.4) | 26.6 | 25.4 | 1.2 (1.1 to 1.3) |
| 2-4 | 58.0 | 58.8 | −0.7 (−0.8 to −0.7) | 56.9 | 57.6 | −0.7 (−0.8 to −0.6) | 56.6 | 57.5 | −1.0 (−1.2 to −0.8) | 61.8 | 62.5 | −0.7 (−0.9 to −0.6) |
| ≥5 | 10.7 | 10.6 | 0.1 (0.1 to 0.2) | 9.4 | 9.2 | 0.2 (0.2 to 0.3) | 17.4 | 13.9 | 3.5 (3.4 to 3.7) | 11.7 | 12.1 | −0.4 (−0.5 to −0.3) |
| Infant sex | ||||||||||||
| Malee | 51.2 | 51.2 | 0.0 (−0.0 to 0.1) | 51.3 | 51.3 | 0.0 (−0.1 to 0.1) | 50.8 | 50.7 | 0.1 (−0.1 to 0.3) | 51.0 | 51.0 | −0.0 (−0.2 to 0.1) |
| Female | 48.8 | 48.8 | −0.0 (−0.1 to 0.0) | 48.7 | 48.7 | −0.0 (−0.1 to 0.1) | 49.2 | 49.3 | −0.1 (−0.3 to 0.1) | 49.0 | 49.0 | 0.0 (−0.1 to 0.2) |
| Father acknowledgedj | 90.4 | 87.6 | 2.8 (2.7 to 2.8) | 94.0 | 92.3 | 1.7 (1.7 to 1.8) | 72.6 | 68.7 | 3.9 (3.8 to 4.1) | 90.0 | 88.7 | 1.3 (1.3 to 1.4) |
The preexpansion period was 2011 through the month of Medicaid expansion in expansion states and was 2011-2014 for nonexpansion states. Medicaid expansion and nonexpansion states are listed in footnote “b” of Table 1.
Number of births in the non-Hispanic white, non-Hispanic black, and Hispanic categories do not sum to the number of births in the overall category because births of any race and ethnicity were included in the overall category.
Percentages may not add up to 100%, and the difference values may not be equal to the expansion minus the nonexpansion value due to rounding.
For subgroup analyses of Medicaid-covered births and Medicaid-covered births to women with at most a high school degree in Table 4, payer type was not included as a covariate. For subgroup analyses of Medicaid-covered births to women with at most a high school degree, the reference category for age was 36 years and older.
Reference category in regression analyses.
The other racial/ethnic category includes births that were not classified as non-Hispanic white, non-Hispanic black, or Hispanic. Hispanic births included births of any racial/ethnic group with a positive indicator for Hispanic ethnicity.
The mother’s age was based on the age at the time of birth minus 1 year to ensure the mother was at least 18 years old at the time of conception.
Underweight, normal weight, and overweight or obese categories were defined as a mother with a prepregnancy body mass index of <18.5, 18.5 to 24.9, and ≥25.0 (calculated by the NCHS as weight in pounds divided by height in inches squared times 703).
Prepregnancy diabetes, prepregnancy hypertension, pregnancy hypertension, and eclampsia are pregnancy risk factors indicated within the Birth Data Files as binary variables and are recommended to be taken directly from the medical record for the birth. Prepregnancy diabetes and prepregnancy hypertension indicate conditions present prior to the pregnancy. Any infection was created as a binary variable equal to 1 if the birth record indicated that the mother had gonorrhea, syphilis, chlamydia, hepatitis B, or hepatitis C present and/or treated during the pregnancy, which are recommended to be taken from the medical record of the birth.
Acknowledgment of a father was created as a binary variable equal to 1 for women who were married at any point during pregnancy or for births with a completed paternal acknowledgment form at the time of the birth certificate documentation completion.