Characteristic | Control (N = 29)a | Case (N = 73)a | P valueb |
---|---|---|---|
Maternal age (years) | 0.703 | ||
 < 25 | 14 (50.0) | 30 (41.1) | |
 25–29 | 6 (21.4) | 20 (27.4) | |
 ≥ 30 | 8 (28.6) | 23 (31.5) | |
BMI (kg/m2) | 0.595 | ||
 < 18.5 | 2 (6.9) | 6 (8.6) | |
 18.5–27.9 | 22 (75.9) | 57 (81.4) | |
 ≥ 28 | 5 (17.2) | 7 (10.0) | |
Maternal education | 0.005 | ||
 Primary or lower | 4 (13.8) | 9 (12.5) | |
 Junior high | 12 (41.4) | 52 (72.2) | |
 High school or above | 13 (44.8) | 11 (15.3) | |
Occupation | < 0.001 | ||
 Farmer | 14 (48.3) | 61 (87.1) | |
 Non-farmer | 15 (51.7) | 9 (12.9) | |
Previous birth defects history | 0.200 | ||
 Yes | 0 | 4 (5.6) | |
 No | 28 (100) | 67 (94.4) | |
Gravidity | 0.219 | ||
 1 | 17 (58.6) | 32 (45.1) | |
 ≥ 2 | 12 (41.4) | 39 (54.9) | |
Parity | 0.060 | ||
 1 | 18 (72.0) | 32 (50.0) | |
 ≥ 2 | 7 (28.0) | 32 (50.0) | |
Periconceptional folic acid supplementation | < 0.001 | ||
 Yes | 4 (14.3) | 42 (60.0) | |
 No | 24 (85.7) | 28 (40.0) | |
Cold or fever | 0.059 | ||
 Yes | 5 (17.9) | 27 (37.5) | |
 No | 23 (82.1) | 45 (62.5) | |
Active or passive smoking | 0.210 | ||
 Yes | 15 (55.6) | 29 (41.4) | |
 No | 12 (44.4) | 41 (58.6) | |
Drinking | 0.940 | ||
 Yes | 17 (65.4) | 47 (66.2) | |
 No | 9 (34.6) | 24 (33.8) | |
Gestational age (weeks) | 0.023 | ||
 < 28 | 14 (48.3) | 52 (72.2) | |
 28–36 | 7 (24.1) | 14 (19.4) | |
 > 36 | 8 (27.6) | 6 (8.3) | |
Fetal sex | 0.129 | ||
 Male | 17 (58.6) | 28 (41.8) | |
 Female | 12 (41.4) | 39 (58.2) |