Table 1.
Socio-demographic, maternal pregnancy, and birth related characteristics for multiparous births by interpregnancy interval and primiparous births.
| 0 to <6months (n=43,549) |
6 to <12months (n=80,504) |
12 to <24months (n=163,934) |
24 to <60months (n=213,154) |
≥60months (n=103,076) |
Primips | p Value | |
|---|---|---|---|---|---|---|---|
| Socio-Demographic Characteristics | |||||||
| Age in years Mean (SD) | 25.6 (5.2) | 27.2 (5.4) | 28.3 (5.3) | 28.9 (5.2) | 31.8 (4.9) | 25.0 (5.7) | p < 0.001 |
| Married | 47.7% | 63.3% | 70.2% | 64.2% | 53.5% | 49.6% | p < 0.001 |
| ≤ High School Education | 27.9% | 21.1% | 15.7% | 13.7% | 12.4% | 15.7% | p < 0.001 |
| Medicaid | 56.6% | 41.7% | 34.1% | 38.3% | 43.1% | 36.7% | p < 0.001 |
| WIC | 58.0% | 42.3% | 34.8% | 38.8% | 45.4% | 43.3% | p < 0.001 |
| Tobacco Use | 29.6% | 22.1% | 19.2% | 23.9% | 31.1% | 22.9% | p < 0.001 |
| ≤ 5 Prenatal Visits | 19.0% | 13.5% | 9.8% | 8.0% | 7.6% | 7.3% | p < 0.001 |
| Non-hispanic White | 69.4% | 76.6% | 80.5% | 76.5% | 70.6% | 77.5% | p < 0.001 |
| Non-hispanic Black | 23.1% | 17.0% | 13.3% | 15.9% | 20.7% | 15.2% | p < 0.001 |
| Hispanic | 5.7% | 4.4% | 3.9% | 4.8% | 5.9% | 4.0% | p < 0.001 |
| Other | 1.5% | 1.8% | 2.1% | 2.6% | 2.6% | 3.1% | p < 0.001 |
| Maternal Pregnancy Characteristics | |||||||
| Parity (Median, IQR) | 2 (0, 4) | 1 (0, 1) | 1 (0, 1) | 1 (0, 1) | 1 (0, 1) | 0 (0, 0) | p < 0.001 |
| Prior preterm birth | 8.4% | 6.7% | 6.0% | 6.3% | 6.8% | 0.0% | p < 0.001 |
| Underweight (BMI < 18.5) | 3.7% | 4.2% | 4.3% | 3.9% | 3.1% | 5.1% | p < 0.001 |
| Obese (BMI > 30) | 29.6% | 24.8% | 22.8% | 26.1% | 31.4% | 20.4% | p < 0.001 |
| Pre-pregnancy BMI (SD) | 27.4 (6.9) | 26.6 (6.7) | 26.2 (6.6) | 26.8 (6.9) | 27.8 (7.3) | 25.8 (6.5) | p < 0.001 |
| Pre-gestational diabetes | 0.7% | 0.7% | 0.7% | 0.9% | 1.5% | 0.8% | p < 0.001 |
| Chronic Hypertension | 1.8% | 1.6% | 1.6% | 2.1% | 3.9% | 1.8% | p < 0.001 |
| Gestational weight gain in pounds (SD) | 27.6 (17.2) | 28.9 (16.8) | 30.1 (16.6) | 30.2 (17.7) | 30.4 (19.0) | 34.4 (17.6) | p < 0.001 |
| Gestational diabetes | 5.2% | 5.0% | 5.1% | 6.5% | 9.7% | 5.1% | p < 0.001 |
| Preeclampsia | 3.7% | 3.6% | 3.6% | 4.4% | 6.3% | 5.8% | p < 0.001 |
| Birth Characteristics | |||||||
| Cesarean Delivery | 27.1% | 27.8% | 28.9% | 31.6% | 34.2% | 30.2% | p < 0.001 |
| Male infant gender | 51.0% | 51.1% | 51.0% | 51.2% | 51.0% | 51.3% | p = 0.635 |
| Gestational age Mean (SD) | 38.4 (2.84) | 38.6 (2.58) | 38.6 (2.35) | 38.5 (2.38) | 38.3 (2.69) | 38.7 (2.75) | p < 0.001 |
| Birth Weight in grams, Mean (SD) | 3210 (606) | 3319 (574) | 3357 (560) | 3320 (574) | 3239 (625) | 3226 (605) | p < 0.001 |
| SGA Births <10% | 11.3% | 8.7% | 7.8% | 8.8% | 11.0% | 12.4% | p < 0.001 |
| LGA Births >90% | 8.9% | 11.4% | 12.4% | 11.6% | 10.6% | 7.8% | p < 0.001 |
| Preterm Birth | 14.7% | 11.6% | 10.1% | 11.0% | 14.0% | 11.8% | p < 0.001 |