Table 1.
Demographic, clinical and genetic characteristics of Black mothers* at the Boston Medical Center, grouped by degree of preterm birth (PTB)**.
| Characteristics | PTB (N=518) | Very PTB (N=211) | Late PTB (N=307) | Control (N=512) |
|---|---|---|---|---|
| Demographic characteristics | ||||
| Mean ± SD | ||||
| Age (yr) | 28.67 ± 6.92 | 28.68 ± 7.07 | 28.67 ± 6.81 | 28.68 ± 6.92 |
| Yr in the US (yr) a | 7.16 ± 7.08 (N=194) | 8.69 ± 8.03 (N=72) | 6.21 ± 6.32 (N=123) | 6.51 ± 6.21 (N=263) |
| Prepregnancy BMI (Kg/m2) | 26.54 ± 6.17 | 26.76 ± 6.04 | 26.37 ± 6.25 | 26.66 ± 5.80 |
| Parity (%) | ||||
| 0 | 43.05 | 42.65 | 43.59 | 38.28 |
| 1 | 25.68 | 25.59 | 25.21 | 31.05 |
| >= 2 | 31.27 | 31.75 | 31.20 | 30.66 |
| Education (%) | ||||
| < High School | 25.78 | 25.73 | 21.46 | 30.63 |
| High School | 41.99 | 43.69 | 39.91 | 31.03 |
| Some college and above | 32.23 | 30.58 | 38.63 | 38.34 |
| Place of birth (%) | ||||
| US | 53.20 | 55.77 | 51.28 | 37.72 |
| Other | 46.80 | 44.23 | 48.72 | 62.28 |
| Smoking (%) | ||||
| Never | 75.53 | 76.08 | 75.11 | 85.35 |
| Quitter | 6.21 | 6.70 | 6.01 | 6.64 |
| Current | 18.25 | 17.22 | 18.88 | 8.01 |
| Illicit drug use (%) | ||||
| No | 81.94 | 81.34 | 83.26 | 90.57 |
| Yes | 18.06 | 18.66 | 16.74 | 9.43 |
| Lifetime stress (%) | ||||
| Not stressed | 29.63 | 29.61 | 30.04 | 36.83 |
| Average | 53.22 | 50.49 | 54.51 | 52.87 |
| Very stressed | 17.15 | 19.90 | 15.45 | 10.30 |
| Stress during pregnancy (%) | ||||
| Not stressed | 29.04 | 28.64 | 29.18 | 39.80 |
| Average | 45.42 | 47.57 | 44.21 | 42.57 |
| Very stressed | 25.54 | 23.79 | 26.61 | 17.62 |
| Clinical characteristics | ||||
| Gestational age (wk) | 33.29 ± 3.58 | 29.76 ± 3.09 | 35.71 ± 0.81 | 39.48 ± 1.30 |
| Birthweight (g) | 2042.73 ± 768.00 | 1367.25 ± 552.33 | 2508.67 ± 506.32 | 3323.38 ± 497.99 |
| Hypertensive disorders (%) | ||||
| No | 69.05 | 60.95 | 76.92 | 92.55 |
| Yes | 30.95 | 39.05 | 23.08 | 7.45 |
| Histologic chorioamnionitis (%) | ||||
| No | 73.59 | 58.29 | 84.85 | 85.74 |
| Yes | 26.41 | 41.71 | 15.15 | 14.26 |
| Diabetes Mellitus (DM) (%) | ||||
| No | 89.75 | 89.10 | 91.42 | 95.11 |
| Yes | 4.06 | 3.79 | 3.00 | 0.78 |
| Gestational DM | 6.19 | 7.11 | 5.58 | 4.11 |
| Placenta abruption (%) | ||||
| No | 91.89 | 85.78 | 97.01 | 99.21 |
| Yes | 8.11 | 14.22 | 2.99 | 0.79 |
| Placenta Previa (%) | ||||
| No | 95.75 | 94.31 | 97.44 | 99.21 |
| Yes | 4.25 | 5.69 | 2.56 | 0.79 |
| Genetic characteristics | ||||
| African ancestry 0.88 (0.15); proportion (mean (sd); median) | 0.88 (0.12); 0.92 | 0.87 (0.16); 0.92 | 0.85 (0.16); 0.92 | 0.89 |
| Genotypes of GSTT1 (%) | ||||
| Present | 75.26 | 76.03 | 74.71 | 70.23 |
| Absent | 24.74 | 23.97 | 25.29 | 29.77 |
| Genotypes of CYP1A1 (%) | ||||
| AA | 59.03 | 61.16 | 57.49 | 59.22 |
| Aa/aa | 40.97 | 38.84 | 42.51 | 40.78 |
Note:
*
Based on self-reported Black race.
**
PTB: preterm birth with gestational age <37 weeks; very PTB: preterm birth with gestational age <34 weeks; late PTB: preterm birth with gestational age 34.0–36.86 weeks.
a
Only used non-US born subjects to calculate year in the US.