Baseline characteristics of gastroschisis cases and controls, National Birth Defects Prevention Study, USA, 1997–2011
| Gastroschisis cases (n=879) | Total controls (n=7817) | |
| N (%) | N (%) | |
| Maternal age at delivery (years)* | ||
| <20 | 246 (28.0%) | 492 (6.3%) |
| 20–24 | 408 (46.4%) | 1747 (22.3%) |
| 25–29 | 161 (18.3%) | 2240 (28.7%) |
| 30–34 | 52 (5.9%) | 2163 (27.7%) |
| ≥35 | 12 (1.4%) | 1176 (15.0%) |
| Maternal education* | ||
| ≤12 years | 498 (56.9%) | 2504 (32.1%) |
| >12 years | 377 (43.1%) | 5300 (67.9%) |
| Maternal race-ethnicity* | ||
| Non-Hispanic white | 503 (57.2%) | 5003 (64.0%) |
| Non-Hispanic black | 83 (9.4%) | 899 (11.5%) |
| Hispanic | 223 (25.4%) | 1433 (18.3%) |
| Other | 70 (8.0%) | 482 (6.2%) |
| Pre-pregnancy BMI (kg/m2)* | ||
| Underweight (<18.5) | 63 (7.3%) | 352 (4.6%) |
| Normal weight (18.5–25) | 603 (69.6%) | 4125 (53.9%) |
| Overweight (25-30) | 159 (18.3%) | 1772 (23.2%) |
| Obese (>30) | 42 (4.8%) | 1403 (18.3%) |
| Parity* | ||
| 0 | 611 (69.5%) | 3514 (45.0%) |
| ≥1 | 268 (30.5%) | 4301 (55.0%) |
| Maternal cigarette smoking during periconceptional period*† | ||
| Yes | 485 (55.2%) | 2498 (32.0%) |
| No | 391 (44.8%) | 5302 (68.0%) |
| Maternal alcohol use during periconceptional period* | ||
| Yes | 429 (48.9%) | 3327 (42.7%) |
| No | 448 (51.2%) | 4464 (56.7%) |
| Maternal illicit drug use during periconceptional period*‡ | ||
| Yes | 117 (13.3%) | 329 (4.2%) |
| No | 761 (86.7%) | 7486 (95.8%) |
Totals do not add up due to missing data.
*Significant difference between cases and controls (p value <0.05) using X2 tests.
†Self-reported cigarette smoking and secondhand cigarette smoke exposure at work and at home.
‡Included marijuana, hash, cocaine, crack, hallucinogens, heroin and mushrooms.
BMI, body mass index;