Table 1. Characteristics of Study Participants in Analytic Sample.
| Characteristics | No. (%) (n = 7495) |
|---|---|
| Maternal characteristics | |
| Age at delivery (n = 7320), mean (SD), y | 29.2 (6.1) |
| Educational level during pregnancy | |
| <4-y College degree | 2151 (28.7) |
| ≥4-y College degree | 2223 (29.7) |
| Missing | 3121 (41.6) |
| Annual household income during pregnancy, $ | |
| <75 000 | 2393 (31.9) |
| ≥75 000 | 512 (6.8) |
| Missing | 4590 (61.2) |
| Prenatal cigarette smoking | |
| Yes | 683 (9.1) |
| No | 4409 (58.8) |
| Missing | 2403 (32.1) |
| Nulliparous | |
| Yes | 1306 (17.4) |
| No | 2033 (27.1) |
| Missing | 4156 (55.5) |
| Gestational diabetes | |
| Yes | 215 (2.9) |
| No | 3596 (48.0) |
| Missing | 3684 (49.2) |
| Gestational hypertension/preeclampsia | |
| Yes | 401 (5.4) |
| No | 4196 (56.0) |
| Missing | 2898 (38.7) |
| Mode of delivery | |
| Vaginal | 3620 (48.3) |
| Cesarean | 1495 (19.9) |
| Missing | 2380 (31.8) |
| Prepregnancy BMI (n = 5032), mean (SD) | 26.5 (6.7) |
| Gestational weight gain (n = 4116), mean (SD), kg | 15.5 (10.5) |
| Gestational age at delivery (n = 6527), mean (SD), wk | 38.2 (3.3) |
| Child characteristics | |
| Birth year | |
| Before 2000 | 1188 (15.9) |
| 2000-2010 | 3884 (51.8) |
| After 2010 | 2423 (32.3) |
| Sex | |
| Male | 3723 (49.7) |
| Female | 3772 (50.3) |
| Race | |
| American Indian or Alaska Native, Native Hawaiian or Pacific Islander, multiple races, or other racea | 868 (11.6) |
| Asian | 120 (1.6) |
| Black | 1705 (22.7) |
| White | 4505 (60.1) |
| Missing | 297 (4.0) |
| Hispanic ethnicity | 1124 (15.0) |
| Missing | 29 (0.4) |
Abbreviation: BMI, body mass index (calculated as weight in kilograms divided by height in meters squared).
a
The other race category was obtained from a survey questionnaire with no further breakdown available.