Table 4.
Multivariate analysis of maternal factors associated with preterm birth
| Maternal factors associated | Cases, n (%) | Controls, n (%) | Crude OR (95% CI) | Adjusted OR (95% CI) | |
|---|---|---|---|---|---|
| History of preterm births | Yes | 37 (17) | 17 (3.9) | 5.1 (2.8–9.2) | 6.4 (2.9–13.9)* |
| No | 181 (83) | 421 (96.1) | 1 | ||
| History of stillbirths | Yes | 34 (15.6) | 34 (7.8) | 2.2 (1.3–3.6) | 4.2 (2–8.9)* |
| No | 184 (84.4) | 404 (92.2) | 1 | ||
| Cardiac disease | yes | 6 (2.8) | 4 (0.9) | 3.1 (0.9–10.9) | 5.2 (0.9–27.7) |
| no | 212 (97.2) | 434 (99.1) | 1 | ||
| Anemia | Yes | 32 (14.7) | 15 (3.4) | 4.8 (2.6–9.2) | 2.7 (1–7.01)*** |
| No | 186 (85.3) | 423 (96.6) | 1 | ||
| APH | Yes | 43 (19.7) | 13 (3) | 8 (4.2–15.3) | 8.1 (3.5–18.5)* |
| No | 175 (80.3) | 425 (97) | 1 | ||
| Preeclampsia | Yes | 69 (31.7) | 22 (5) | 8.8 (5.2–14.7) | 6.6 (3.3–13.4)* |
| No | 149 (68.3) | 416 (95) | 1 | ||
| PROM | Yes | 70 (32.1) | 23 (5.3) | 8.5 (5.1–14.2) | 11.7 (6.2–21.9)* |
| No | 148 (67.9) | 415 (94.7) | 1 | ||
| PIH | Yes | 39 (17.9) | 8 (1.8) | 11.7 (5.4–25.6) | 6 (2.3–15.6)* |
| No | 179 (82.1) | 430 (98.2) | 1 | ||
| Hemoglobin level | <11 mg/dL | 78 (35.8) | 49 (11.2) | 4.4 (2.9–6.6) | 2.2 (1.2–4.1)*** |
| ≥11 mg/dL | 140 (64.2) | 389 (88.8) | 1 | ||
| Multiple pregnancies | Yes | 51 (23.4) | 37 (8.4) | 3.3 (2.1–5.2) | 4.5 (2.4–8.5)* |
| No | 167 (76.6) | 401 (91.6) | 1 | ||
| Birth interval | <2 years | 105 (48.2) | 127 (29) | 2.3 (1.6–3.2) | 2.7 (1.7–4.5)* |
| ≥2 years | 113 (51.8) | 311 (71) | 1 | ||
| Number of ANC visits | None | 11 (5) | 13 (3) | 5.4 (1.6–17.4) | 3.4 (0.6–20.5) |
| ≤4 | 201 (92.2) | 387 (88.4) | 3.3 (1.4–7.9) | 4.8 (1.2–19)*** | |
| ≥5 | 6 (2.8) | 38 (8.7) | 1 | ||
Notes: By backward removal analysis, reference category for logistic regression represented by 1.
*
P<0.0001;
***
P<0.05.
Abbreviations: ANC, antenatal care; APH, antepartum hemorrhage; PIH, pregnancy-induced hypertension; PROM, prolonged rupture of membrane.