Table 1.
Sample demographics and risk factors
| Study population | Preterm sample | Full-term sample | Chi-square p-value | |
|---|---|---|---|---|
|
| ||||
| Number of pregnancies | 11,320 | 1,256 | 10,064 | |
| Maternal demographics | ||||
| Age at delivery, N (%) with data | 11,320 (100%) | 1,256 (100%) | 10,064 (100%) | <0.05 |
| Mean (SD) | 29 (18–52, 5.9) | 29 (18–52, 6.3) | 29 (18–51, 5.8) | |
| Race, N (%) with data | 10,561 (93%) | 1,166 (93%) | 9,395 (93%) | <0.001 |
| White, N (%) | 5,719 (54%) | 537 (46%) | 5,182 (55%) | |
| Black or African American, N (%) | 2,719 (26%) | 343 (29%) | 2,376 (25%) | |
| Asian, N (%) | 478 (5%) | 60 (5%) | 418 (4%) | |
| Native Hawaiian or other Pacific Islander, N (%) | 68 (<1%) | 9 (<1%) | 59 (<1%) | |
| American Indian or Alaska Native, N (%) | 215 (2%) | 25 (2%) | 190 (2%) | |
| More than one race, N (%) | 729 (7%) | 108 (9%) | 621 (7%) | |
| Other race, N (%) | 633 (6%) | 84 (7%) | 549 (6%) | |
| Ethnicity, N (%) with data | 11,206 (99%) | 1,228 (98%) | 9,978 (99%) | <0.05 |
| Hispanic, N (%) | 2,968 (26%) | 336 (27%) | 2,632 (26%) | |
| Non-Hispanic, N (%) | 8,238 (74%) | 892 (73%) | 7,346 (74%) | |
| Socioeconomic status | ||||
| Prenatal education, N (%) with data | 9,172 (81%) | 1,027 (82%) | 8,145 (81%) | <0.001 |
| < High school, N (%) | 917 (10%) | 124 (12%) | 793 (10%) | |
| High school degree, GED or equivalent, N (%) | 1,930 (21%) | 244 (24%) | 1,686 (21%) | |
| Some college (no degree); associates degree; trade school, N (%) | 2,010 (22%) | 295 (29%) | 1,715 (21%) | |
| Bachelor’s degree, N (%) | 2,282 (25%) | 203 (20%) | 2,079 (26%) | |
| Master’s degree, N (%) | ||||
| Professional or doctorate degree, N (%) | 2,033 (22%) | 161 (16%) | 1,872 (23%) | |
| Prenatal employment, N (%) with data | 4,572 (40%) | 389 (31%) | 4,183 (42%) | <0.001 |
| Employed, N (%) | 3,603 (79%) | 298 (77%) | 3,305 (79%) | |
| Prenatal marital status, N (%) with data | 9,094 (80%) | 995 (79%) | 8,099 (80%) | Not significant |
| Married or living with a partner, N (%) | 6,779 (75%) | 708 (71%) | 6,071 (75%) | |
| Insurance type, N (%) with data | 5,203 (46%) | 464 (37%) | 4,739 (47%) | <0.05 |
| Any private, market, work insurance, N (%) | 2,765 (53%) | 223 (48%) | 2,542 (54%) | |
| Medicare/Medicaid, N (%) | 2,452 (47%) | 241 (52%) | 2,211 (47%) | |
| Other, N (%) | 1,176 (23%) | 97 (21%) | 1,079 (23%) | |
| No Insurance, N (%) | 96 (2%) | 14 (3%) | 82 (2%) | |
| Substance use during pregnancy | ||||
| Alcohol, N (%) with data | 9,696 (86%) | 1,113 (89%) | 8,583 (85%) | <0.001 |
| Yes, N (%) | 1,368 (14%) | 101 (9%) | 1,267 (15%) | |
| Tobacco, N (%) with data | 10,329 (91%) | 1,177 (94%) | 9,152 (91%) | <0.001 |
| Yes, N (%) | 865 (8%) | 124 (11%) | 741 (8%) | |
| Marijuana, N (%) with data | 8,073 (71%) | 996 (79%) | 7,077 (70%) | <0.001 |
| Yes, N (%) | 345 (4%) | 68 (7%) | 277 (4%) | |
| Complications during pregnancy | ||||
| Gestational diabetes, N (%) with data | 8,109 (72%) | 848 (68%) | 7,261 (72%) | <0.001 |
| Yes, N (%) | 689 (8%) | 93 (11%) | 596 (8%) | |
| Preeclampsia, N (%) with data | 8,451 (75%) | 988 (79%) | 7,463 (74%) | <0.001 |
| Yes, N (%) | 462 (5%) | 206 (21%) | 256 (3%) | |
| Neonatal Intensive Care Unit admission, N (%) with data | 2,023 (18%) | 516 (41%) | 1,507 (15%) | <0.001 |
| Yes, N (%) | 565 (28%) | 441 (85%) | 124 (8%) | |
| Prenatal depression, N (%) with data | 4,531 (40%) | 663 (53%) | 3,868 (38%) | <0.05 |
| Yes, N (%) | 565 (12%) | 77 (12%) | 488 (13%) | |
| Prenatal anxiety, N (%) with data | 2,657 (23%) | 510 (41%) | 2,147 (21%) | <0.05 |
| Yes, N (%) | 201 (8%) | 34 (7%) | 167 (8%) | |
| Parity, N (%) with data | 5,178 (46%) | 576 (46%) | 4,602 (46%) | Not significant |
| 0, N (%) | 2,307 (45%) | 266 (46%) | 2,041 (44%) | |
| 1, N (%) | 1,663 (32%) | 170 (30%) | 1,493 (32%) | |
| 2, N (%) | 784 (15%) | 85 (15%) | 699 (15%) | |
| >2, N (%) | 424 (8%) | 55 (10%) | 369 (8%) | |
| Calendar year of child’s birth, N (%) with data | 11,320 (100%) | 1,256(100%) | 10,064 (100%) | <0.001 |
| 1980–2000, N (%) | 19 (<1%) | <5 (<1%) | <19 (1%) | |
| 2001–2010, N (%) | 2,304 (20%) | 182 (14%) | 2,122 (21%) | |
| 2011–2015, N (%) | 2,959 (26%) | 337 (27%) | 2,622 (26%) | |
| 2016–2020, N (%) | 3,733 (33%) | 338 (31%) | 3,345 (33%) | |