Table 1. Characteristics of study subjects.
| Unexposed1 | Opium user | ||||
|---|---|---|---|---|---|
| All | Opium user only | Tobacco and Opium user | |||
| N (%) | N (%) | N (%) | N (%) | ρ-value2 | |
| 905 (100) | 887 (100) | 677 (100) | 210 (100) | ||
| Maternal age (Years) | < .0001 | ||||
| ≤ 19 | 134 (14.8) | 49 (5.5) | 40 (5.9) | 9 (4.3) | |
| 20–24 | 250 (27.6) | 161 (18.2) | 133 (19.6) | 28 (13.3) | |
| 25–29 | 260 (28.7) | 278 (31.3) | 210 (31.0) | 68 (32.4) | |
| 30–34 | 187 (20.7) | 251 (28.3) | 181 (26.7) | 70 (33.3) | |
| ≥ 35 | 68 (7.5) | 143 (16.1) | 108 (16.0) | 35 (16.7) | |
| Maternal height (cm) | 0.9272 | ||||
| ≤ 149 | 68 (7.5) | 66 (7.4) | 47 (6.9) | 19 (9.0) | |
| 150–155 | 198 (21.9) | 193 (21.8) | 152 (22.5) | 41 (19.5) | |
| 156–160 | 380 (42.0) | 399 (45.0) | 295 (43.6) | 104 (49.5) | |
| 161–164 | 120 (13.3) | 109 (12.3) | 84 (12.4) | 25 (11.9) | |
| ≥ 165 | 100 (11.0) | 103 (11.6) | 86 (12.7) | 17 (8.1) | |
| Maternal body mass index | 0.4830 | ||||
| < 18.5 | 63 (7.0) | 52 (5.9) | 34 (5.0) | 18 (8.6) | |
| 18.5 to < 25 | 439 (48.5) | 474 (53.4) | 356 (52.6) | 118 (56.2) | |
| 25 to < 30 | 245 (27.1) | 231 (26.0) | 184 (27.2) | 47 (22.4) | |
| 30 to < 35 | 91 (10.1) | 91 (10.3) | 72 (10.6) | 19 (9.0) | |
| ≥ 35 | 28 (3.1) | 21 (2.4) | 18 (2.7) | 3 (1.4) | |
| Parity | < .0001 | ||||
| Nulliparous | 372 (41.1) | 199 (22.4) | 155 (22.9) | 44 (21.0) | |
| Multiparous | 533 (58.9) | 688 (77.6) | 522 (77.1) | 166 (79.0) | |
| Delivery method | 0.2541 | ||||
| Vaginal delivery | 559 (61.8) | 572 (64.5) | 428 (63.2) | 144 (68.6) | |
| Caesarean section | 320 (35.4) | 292 (32.9) | 234 (34.6) | 58 (27.6) | |
| Husband’s occupation | 0.0023 | ||||
| Unemployed | 25 (2.8) | 56 (6.3) | 37 (5.5) | 19 (9.0) | |
| Non skill worker | 400 (44.2) | 419 (47.2) | 312 (46.1) | 107 (51.0) | |
| Skill worker | 91 (10.1) | 70 (7.9) | 58 (8.6) | 12 (5.7) | |
| Self-employed | 111 (12.3) | 101 (11.4) | 89 (13.1) | 12 (5.7) | |
| Farmer | 179 (19.8) | 163 (18.4) | 123 (18.2) | 40 (19.0) | |
| Other | 95 (10.5) | 69 (7.8) | 52 (7.7) | 17 (78.1) | |
| Hypertension during pregnancy | 0.8906 | ||||
| Yes | 28 (3.1) | 26 (2.9) | 19 (2.8) | 7 (3.3) | |
| No | 877 (96.9) | 861 (97.1) | 658 (97.2) | 203 (96.7) | |
| Gestational age weeks (weeks) | < .0001 | ||||
| Mean (SD) | 39.3 (1.6) | 39.1 (1.9) | 39.0 (1.9) | 38.7 (2.1) | |
| Median (Range) | 39 (29–43) | 39 (28–42) | 39 (29–42) | 39 (28–42) | |
| Birth of an infant small for gestational age | < .0001 | ||||
| Yes | 105 (11.6) | 164 (18.5) | 125 (18.5) | 39 (18.6) | |
| No | 785 (86.6) | 713 (80.2) | 543 (80.2) | 170 (81.0) | |
1Unexposed includes mothers who are non-users of both opium and tobacco.
2ρ-value of unexposed group comparing with all exposed.