Table 1.
Distributions of demographic characteristics in study population: N (%).
| Characteristic | Term | Preterm | Spontaneous preterm | Placental preterm | |
|---|---|---|---|---|---|
| Race/ethnicity (missing = 0) | White | 207 (58.8) | 75 (57.7) | 30 (53.6) | 20 (57.1) |
| African American | 55 (15.6) | 22 (16.9) | 8 (14.3) | 8 (22.9) | |
| Other | 90 (25.6) | 33 (25.4) | 18 (32.1) | 7 (20.0) | |
| Education (missing = 11) | High school | 47 (13.7) | 21 (16.3) | 7 (12.5) | 10 (28.6) |
| Technical school | 52 (15.2) | 25 (19.4) | 12 (21.4) | 5 (14.3) | |
| Junior college/some college | 101 (29.5) | 38 (29.5) | 16 (28.6) | 12 (34.3) | |
| College graduate | 142 (41.5) | 45 (34.9) | 21 (37.5) | 8 (22.9) | |
| Health insurance (missing = 12) | Private/HMO/self-pay | 277 (81.0) | 108 (84.4) | 48 (85.7) | 26 (78.8) |
| Medicaid/SSI/MassHealth | 65 (19.0) | 20 (15.6) | 8 (14.3) | 7 (21.2) | |
| BMI (missing = 4) | <25 kg/m2 | 188 (54.0) | 62 (47.7) | 30 (53.6) | 8 (22.9)a |
| 25–30 kg/m2 | 94 (27.0) | 32 (24.6) | 15 (26.8) | 9 (25.7)a | |
| ≥30 kg/m2 | 66 (19.0) | 36 (27.7) | 11 (19.6) | 18 (51.4)a | |
| Tobacco use (missing =6) | Yes | 20 (5.8) | 11 (8.5) | 4 (7.2) | 7 (20.0)a |
| No | 326 (94.2) | 119 (91.5) | 52 (92.8) | 28 (80.0)a | |
| Alcohol use (missing = 10) | Yes | 19 (5.5) | 1 (0.8)a | 0 (0) | 0 (0) |
| No | 326 (94.5) | 126 (99.2)a | 54 (100) | 35 (100) | |
| Parity (missing = 0) | Nulliparous | 160 (45.5) | 55 (42.3) | 24 (42.9) | 20 (57.1) |
| Parous | 192 (54.5) | 75 (57.7) | 32 (57.1) | 15 (42.9) | |
| Gender (missing = 0) | Male | 158 (44.9) | 56 (43.1) | 27 (48.2) | 16 (45.7) |
| Female | 194 (55.1) | 74 (56.9) | 29 (51.8) | 19 (54.3) | |
| Use of ART (missing = 0) | Yes | 33 (9.4) | 12 (9.2) | 4 (7.1) | 4 (11.4) |
| No | 319 (90.6) | 118 (90.8) | 42 (92.9) | 31 (88.6) | |
Abbreviations: BMI, body mass index; HMO, health maintenance organization; SSI, supplemental security income; ART, assisted reproductive technology.
a
P <0.05 for χ2 test comparing distributions in overall, spontaneous, or placental preterm vs. term groups.