Table 3 Association of some obstetrics variables with preterm delivery before 37 weeks in singleton pregnancies (N = 371)
Variable | N | Preterm birth (n = 188) | ||
|---|---|---|---|---|
n (%) | cOR (95% CI)a | Pb | ||
Gravida | ||||
Primigravida | 150 | 74 (49.3) | 0.96 (0.63 to 1.46) | 0.866 |
2–5 | 213 | 107 (50.2) | Reference | |
6 or more | 8 | 7 (87.5) | 6.93 (0.84 to 57.34) | 0.072 |
Previous Caesarean section | ||||
No | 295 | 152 (51.5) | Reference | |
Yes | 76 | 36 (47.4) | 0.85 (0.51 to 1.40) | 0.518 |
Last childbirth intervalc | ||||
> 12 months | 160 | 79 (49.4) | Reference | |
≤ 12 months | 22 | 14 (63.6) | 1.80 (0.71 to 4.51) | 0.214 |
Previous abortion | ||||
No | 266 | 131 (49.2) | Reference | |
Yes | 105 | 57 (54.3) | 1.22 (0.79 to 1.92) | 0.382 |
History of preterm birth | ||||
No | 312 | 152 (48.7) | Reference | |
Yes | 59 | 36 (61.0) | 1.65 (0.93 to 2.91) | 0.085 |
Gestational age (weeks) | ||||
> 32 | 212 | 104 (49.1) | Reference | |
28 - 32 | 118 | 57 (48.3) | 0.97 (0.62 to 1.52) | 0.896 |
< 28 | 41 | 27 (65.9) | 2.00 (0.99 to 4.03) | 0.052 |
Spontaneous pregnancy | ||||
Yes | 309 | 152 (49.2) | Reference | |
No | 62 | 36 (58.1) | 1.43 (0.82 to 2.48) | 0.204 |
Abnormal result(s) in routine early pregnancy tests | ||||
No | 214 | 102 (47.7) | Reference | |
Yes | 157 | 86 (54.8) | 1.33 (0.88 to 2.01) | 0.176 |
Weight gain during pregnancy | ||||
Normal | 76 | 34 (44.7) | Reference | |
Less than normal | 239 | 128 (53.6) | 1.42 (0.85 to 2.39) | 0.181 |
Over normal | 56 | 26 (46.4) | 1.07 (0.53 to 2.14) | 0.847 |
Physical trauma during pregnancy | ||||
No | 330 | 166 (50.3) | Reference | |
Yes | 41 | 22 (53.7) | 1.14 (0.60 to 2.19) | 0.685 |
Infected disease during pregnancy | ||||
No | 58 | 29 (50.0) | Reference | |
Yes | 313 | 159 (50.8) | 1.03 (0.59 to 1.81) | 0.911 |
Thyroid disorder during pregnancy | ||||
No | 330 | 165 (50.0) | Reference | |
Yes | 41 | 23 (56.1) | 1.28 (0.66 to 2.45) | 0.462 |
Sexual intercourse during last week before admission | ||||
No | 258 | 138 (53.5) | Reference | |
Yes | 113 | 50 (44.2) | 0.69 (0.44 to 1.07) | 0.102 |
History of vaginal bleeding or spotting during the current pregnancy | ||||
No | 221 | 102 (46.2) | Reference | |
Yes | 150 | 86 (57.3) | 1.57 (1.03 to 2.38) | 0.035 |
Leukocytosis at admission | ||||
No | 338 | 167 (49.4) | Reference | |
Yes | 33 | 21 (63.6) | 1.79 (0.85 to 3.76) | 0.123 |
Hemoglobin | ||||
≥ 11 | 327 | 165 (50.5) | Reference | |
< 11 | 44 | 23 (52.3) | 1.07 (0.57 to 2.02) | 0.821 |
Vaginal bleeding or spotting at admission | ||||
No | 291 | 142 (48.8) | Reference | |
Yes | 80 | 46 (57.5) | 1.42 (0.86 to 2.34) | 0.169 |
Rupture of membranes at admission | ||||
No | 296 | 123 (41.6) | Reference | |
Yes | 75 | 65 (86.7) | 9.14 (4.52 to 18.50) | < 0.001 |
Cervical dilatation | ||||
No | 135 | 45 (38.9) | Reference | |
Yes | 236 | 143 (60.6) | 3.07 (1.97 to 4.79) | < 0.001 |
Uterine contraction | ||||
No | 95 | 41 (43.2) | Reference | |
Yes | 276 | 147 (53.3) | 1.50 (0.94 to 2.40) | 0.090 |