TABLE 1.
Maternal demographics and baseline characteristics
| Demographics and characteristics | UnderweightBMI <18.5 (%) | Normal weight/overweightBMI 18.5–29.9 (%) | Class 1 obesityBMI 30–≤35 (%) | Class 2 obesityBMI 35–≤40 (%) | Class 3 obesityBMI 40–≤50 (%) | Super obesityBMI ≥50 (%) | P value |
|---|---|---|---|---|---|---|---|
| N | 31,697 | 445,398 | 59,167 | 22,162 | 11,277 | 1296 | |
| Deliveries | 5.6 | 78.0 | 10.4 | 3.9 | 2.0 | 0.2 | |
| Maternal age, y | |||||||
| <20 | 7.4 | 5.8 | 5.4 | 4.8 | 4.5 | 2.5 | <.001 |
| 20–29 | 53.0 | 44.4 | 46.1 | 47.9 | 48.0 | 48.2 | |
| 30–34 | 24.6 | 28.1 | 26.4 | 26.0 | 26.4 | 28.5 | |
| 35–39 | 12.2 | 16.8 | 16.6 | 16.0 | 16.1 | 15.1 | |
| 40–44 | 2.6 | 4.5 | 5.0 | 5.1 | 4.7 | 5.5 | |
| >45 | 0.2 | 0.4 | 0.4 | 0.3 | 0.4 | 0.2 | |
| Race and ethnicity | |||||||
| Black non-Hispanic | 13.3 | 18.3 | 33.6 | 39.3 | 44.0 | 55.3 | <.001 |
| White non-Hispanic | 32.9 | 32.9 | 18.1 | 16.0 | 14.6 | 11.4 | |
| Puerto Rican | 5.2 | 6.7 | 12.1 | 15.0 | 17.0 | 17.3 | |
| Hispanic (other) | 13.7 | 24.0 | 28.7 | 24.9 | 20.9 | 13.5 | |
| Asian or Pacific Islander | 32.8 | 16.3 | 5.8 | 3.0 | 1.7 | 0.8 | |
| Other | 0.5 | 0.4 | 0.4 | 0.4 | 0.2 | 0.5 | |
| Non-Hispanic, ≥2 races | 1.4 | 1.3 | 1.2 | 1.3 | 1.5 | 1.0 | |
| Missing or unknown | 0.1 | 0.1 | 0.1 | 0.1 | 0.1 | 0.2 | |
| Smoked during pregnancy | 0.9 | 0.9 | 1.5 | 1.7 | 2.3 | 3.2 | <.001 |
| Maternal education | |||||||
| Less than HS | 23.7 | 22.6 | 28.2 | 27.7 | 27.6 | 28.3 | <.001 |
| HS | 22.8 | 22.0 | 25.9 | 26.7 | 26.2 | 29.5 | |
| Some college | 19.3 | 20.8 | 27.2 | 29.0 | 31.0 | 31.0 | |
| College graduate or higher | 34.0 | 34.4 | 18.5 | 16.3 | 15.0 | 10.9 | |
| Missing | 0.2 | 0.2 | 0.3 | 0.4 | 0.3 | 0.3 | |
| Insurance | |||||||
| Private | 37.8 | 39.8 | 28.1 | 27.7 | 27.3 | 23.7 | <.001 |
| Medicaid | 58.6 | 56.2 | 66.8 | 67.4 | 67.9 | 71.3 | |
| Other | 1.4 | 1.6 | 2.2 | 2.0 | 1.9 | 1.9 | |
| Self-pay | 1.3 | 1.3 | 1.6 | 1.5 | 1.6 | 1.5 | |
| Missing | 0.5 | 0.5 | 0.6 | 0.6 | 0.5 | 0.8 | |
| Neighborhood poverty level | |||||||
| <10% (low poverty) | 16.1 | 15.1 | 9.2 | 8.9 | 8.8 | 8.0 | <.001 |
| 10%–20% | 30.2 | 29.3 | 26.3 | 24.5 | 22.9 | 20.8 | |
| 20%–<30% | 27.4 | 25.9 | 29.1 | 29.5 | 29.3 | 30.0 | |
| >30% (high poverty) | 19.4 | 21.8 | 30.1 | 32.0 | 34.7 | 37.1 | |
| Non-New York City residents or missing | 7.0 | 8.0 | 5.4 | 5.0 | 4.3 | 4.1 | |
| Prenatal care adequacy | |||||||
| Inadequate | 17.1 | 16.4 | 18.9 | 18.7 | 19.5 | 22.5 | <.001 |
| Intermediate | 10.9 | 11.7 | 10.6 | 10.4 | 10.4 | 10.7 | |
| Adequate | 42.4 | 42.6 | 37.7 | 36.9 | 34.9 | 30.3 | |
| Intensive | 26.2 | 25.8 | 28.5 | 29.4 | 30.3 | 30.9 | |
| Missing | 3.4 | 3.5 | 4.3 | 4.6 | 4.8 | 5.7 | |
| Parity | |||||||
| 0 | 56.8 | 47.3 | 36.3 | 36.3 | 36.5 | 36.9 | <.001 |
| 1 previous | 43.1 | 52.7 | 63.6 | 63.6 | 63.3 | 63.0 | |
| Missing | 0.1 | 0.1 | 0.1 | 0.1 | 0.2 | 0.2 | |
| Delivery method | |||||||
| Primary cesarean delivery | 15.0 | 18.6 | 22.4 | 25.8 | 28.8 | 32.1 | <.001 |
| Repeat cesarean delivery | 6.0 | 10.8 | 17.6 | 20.1 | 23.2 | 26.5 | |
| Vaginal delivery | 77.4 | 68.7 | 57.9 | 52.2 | 46.2 | 39.9 | |
| Vaginal birth after cesarean | 1.2 | 1.7 | 1.9 | 1.8 | 1.6 | 1.9 | |
| Missing | 0.4 | 0.2 | 0.2 | 0.1 | 0.2 | 0.2 | |
| Pregestational diabetesa | 0.2 | 0.5 | 1.6 | 2.5 | 3.8 | 4.4 | <.001 |
| Chronic hypertensiona | 0.3 | 1.2 | 4.2 | 7.0 | 11.0 | 17.2 | <.001 |
| Chronic heart diseasea | 0.5 | 0.4 | 0.3 | 0.2 | 0.2 | 0.3 | <.001 |
BMI, body mass index; HS, high school.
a
These comorbidities were not included in the adjusted analysis.