Table 1.
Socio-demographic and clinical characteristics of the SMO cases and controls
| Cases (%) | Controls (%) | Total | Chi-square | P-value | |
|---|---|---|---|---|---|
| Age | |||||
| < 20 | 16 (7.5) | 15 (3.5) | 31 (4.8) | 22.02 | 0.000 |
| 20–35 | 145 (67.8) | 359 (83.9) | 504 (78.5) | ||
| > 35 | 53 (28.4) | 54 (12.6) | 107 (16.7) | ||
| Marital statusa (N = 630) | |||||
| Married | 182 (85.0) | 402 (94.4) | 584 (91.3) | 15.49 | 0.000 |
| Unmarried | 32 (15.0) | 24 (5.6) | 56 (8.8) | ||
| Professiona (N = 641) | |||||
| Farmer | 200 (93.5) | 423 (99.1) | 623 (97.2) | 17.92 | 0.000 |
| Other profession | 5 (2.3) | 3 (0.7) | 8 (1.2) | ||
| Unemployed | 9 (4.2) | 1 (0.2) | 10 (1.6) | ||
| Education levela (N = 637) | |||||
| Never been to school | 15 (7.1) | 21 (4.9) | 36 (5.7) | 7.36 | 0.25 |
| Primary education | 174 (82.5) | 327 (76.8) | 501 (78.6) | ||
| Secondary and higher | 22 (10.4) | 78 (18.3) | 100 (15.7) | ||
| Medical Insurance | |||||
| No | 13 (6.1) | 38 (8.9) | 51(7.9) | 1.53 | 0.216 |
| Yes | 201 (93.9) | 390 (91.1) | 591 (92.1) | ||
| Clinical characteristics | |||||
| Parity | |||||
| 0 | 60 (28.0) | 179 (41.8) | 239 (37.2) | 15.18 | 0.002 |
| 1 | 41 (19.2) | 78 (18.2) | 119 (18.5) | ||
| 2 to 4 | 84 (39.3) | 140 (32.7) | 224 (34.9) | ||
| ≥ 5 | 29 (13.6) | 31 (7.2) | 60 (9.3) | ||
| Gravidity | |||||
| 1 | 65 (30.4) | 181 (42.3) | 246 (38.3) | 13.25 | 0.001 |
| 2 to 4 | 105 (49.1) | 197 (46.0) | 302 (47.0) | ||
| ≥ 5 | 44 (20.6) | 50 (11.7) | 94 (14.6) | ||
| Previous C/S | |||||
| No | 152 (71.0) | 325 (75.9) | 477 (74.3) | 1.80 | 0.18 |
| Yes | 62 (29.0) | 103 (24.1) | 165 (25.7) | ||
| Previous abortion | |||||
| No | 204 (95.3) | 401 (93.7) | 605 (94.2) | 0.70 | 0.402 |
| Yes | 10 (4.7) | 27 (6.3) | 37 (5.8) | ||
| ANCa (N = 626) | |||||
| 0 | 55 (27.4) | 44 (10.4) | 99 (15.8) | 31.91 | 0.000 |
| 1 | 27 (13.4) | 50 (11.8) | 77 (12.3) | ||
| 2 to 3 | 95 (47.3) | 263 (61.9) | 358 (57.2) | ||
| ≥ 4 | 24 (11.9) | 68 (16) | 92 (14.7) | ||
| Gestational agea (N = 594) | |||||
| < 24 weeks | 40 (21.7) | 1 (0.2) | 41 (6.9) | 179.67 | 0.000 |
| 24–36 weeks | 34 (18.5) | 1 (0.2) | 35 (5.9) | ||
| ≥ 37 weeks | 110 (59.8) | 408 (99.5) | 518 (87.2) | ||
| Outcomes | |||||
| Baby’s condition at birtha (N = 568) | |||||
| Alive (501) | 76 (53.9) | 425 (99.5) | 501 (88.2) | 212.13 | 0.000 |
| Still birth (67) | 65 (46.1) | 2 (0.5) | 67 (11.8) | ||
| Mode of deliverya (N = 532) | |||||
| Vaginal delivery (n = 274) | 44 (45.8) | 230 (53.9) | 274 (52.4) | 2.03 | 0.155 |
| Caesarean section (n = 249) | 52 (54.2) | 197 (46.1) | 249 (47.6) | ||
| Length of hospital staya (N = 641) | |||||
| 0 to 1 day | 17 (8) | 140 (32.7) | 157 (24.5) | 104.97 | 0.000 |
| 2 to 3 days | 47 (22.1) | 152 (35.5) | 199 (31.0) | ||
| 4 to 7 days | 126 (59.2) | 132 (30.8) | 258 (40.2) | ||
| More than 7 days | 23 (10.8) | 4 (0.9) | 27 (4.2) | ||
a Missing information for some cases