From: Maternal preterm birth prediction in the United States: a case-control database study
Variables | Univariate | Multivariate | ||
---|---|---|---|---|
OR (95%CI) | P | OR (95%CI) | P | |
Age | ||||
 < 35 years | Ref |  | Ref |  |
 ≥ 35 years | 1.30 (1.28–1.32) | < 0.001 | 1.27 (1.26–1.29) | < 0.001 |
Race | ||||
 White | Ref |  | Ref |  |
 Black | 1.57 (1.55–1.59) | < 0.001 | 1.26 (1.23–1.29) | < 0.001 |
 Others | 1.04 (1.02–1.06) | < 0.001 | 1.05 (1.03–1.07) | < 0.001 |
Education | ||||
 High school or below | Ref |  | Ref |  |
 Bachelor | 0.76 (0.75–0.77) | < 0.001 | 0.82 (0.81–0.84) | < 0.001 |
 Master or above | 0.76 (0.74–0.77) | < 0.001 | 0.82 (0.81–0.83) | < 0.001 |
Age of spouse | ||||
 < 35 years | Ref |  | Ref |  |
 ≥ 35 years | 1.03 (1.02–1.04) | < 0.001 | 0.98 (0.97–0.99) | < 0.001 |
Race of spouse | ||||
 White | Ref |  | Ref |  |
 Black | 1.53 (1.51–1.55) | < 0.001 | 1.15 (1.12–1.18) | < 0.001 |
 Others | 1.10 (1.08–1.11) | < 0.001 | 1.12 (1.10–1.14) | < 0.001 |
Education of spouse | ||||
 High school or below | Ref |  | Ref |  |
 Bachelor | 0.76 (0.75–0.77) | < 0.001 | 0.86 (0.84–0.87) | < 0.001 |
 Master or above | 0.73 (0.71–0.74) | < 0.001 | 0.82 (0.80–0.84) | < 0.001 |
Pre-pregnancy BMI | ||||
 Normal | Ref |  | Ref |  |
 Underweight | 1.24 (1.21–1.28) | < 0.001 | 1.26 (1.22–1.30) | < 0.001 |
 Overweight | 1.09 (1.08–1.11) | < 0.001 | 0.96 (0.95–0.98) | < 0.001 |
 Obesity | 1.30 (1.29–1.32) | < 0.001 | 0.94 (0.93–0.96) | < 0.001 |
Prenatal care | ||||
 No | Ref |  | Ref |  |
 Yes | 0.48 (0.47–0.50) | < 0.001 | 0.48 (0.47–0.50) | < 0.001 |
Pregnancy smoking | ||||
 No | Ref |  | Ref |  |
 Yes | 1.42 (1.39–1.46) | < 0.001 | 1.27 (1.24–1.30) | < 0.001 |
Pre-pregnancy diabetes | ||||
 No | Ref |  | Ref |  |
 Yes | 2.78 (2.67–2.88) | < 0.001 | 2.08 (1.99–2.16) | < 0.001 |
Gestation diabetes | ||||
 No | Ref |  | Ref |  |
 Yes | 1.47 (1.44–1.49) | < 0.001 | 1.27 (1.24–1.29) | < 0.001 |
Pre-pregnancy hypertension | ||||
 No | Ref |  | Ref |  |
 Yes | 2.52 (2.45–2.59) | < 0.001 | 2.22 (2.16–2.29) | < 0.001 |
Gestation hypertension | ||||
 No | Ref |  | Ref |  |
 Yes | 2.61 (2.57–2.65) | < 0.001 | 2.49 (2.45–2.53) | < 0.001 |
Hypertension eclampsia | ||||
 No | Ref |  | Ref |  |
 Yes | 5.01 (4.70–5.35) | < 0.001 | 4.12 (3.83–4.42) | < 0.001 |
Previous preterm birth | ||||
 No | Ref |  | Ref |  |
 Yes | 3.43 (3.36–3.50) | < 0.001 | 2.95 (2.88–3.01) | < 0.001 |
Previous cesareans | ||||
 No | Ref |  | Ref |  |
 Yes | 1.29 (1.28–1.31) | < 0.001 | 1.13 (1.11–1.14) | < 0.001 |
Infections | ||||
 No | Ref |  | Ref |  |
 Yes | 1.30 (1.26–1.35) | < 0.001 | 1.12 (1.08–1.16) | < 0.001 |
Plurality | ||||
 No | Ref |  | Ref |  |
 Yes | 12.71 (12.47–12.95) | < 0.001 | 12.99 (12.73–13.24) | < 0.001 |