| Study | Study type | Country | Number of infants | Relative risk (95%
confidence interval) of malformations | |
|---|---|---|---|---|---|
| Shiono et al. 1986a | Cohort | United States | 33,434 | Nonsmokers | 1.0 |
| Smokers | |||||
| Major malformation of infant | 1.0 (0.8-1.2) | ||||
| Minor malformation of infant | 0.9 (0.8-0.9) | ||||
| Malloy et al. 1989 | Cohort | United States | 288,067 | Nonsmokers | 1.0 |
| Smokers | |||||
| All birth defects | 0.98 (0.94-1.03) | ||||
| Seidman et al. 1990 | Cohort | Israel | 17,152 | Nonsmokers | 1.0 |
| Smokers | |||||
| Major malformation of infant | 0.9 (0.6-1.4) | ||||
| Minor malformation of infant | 1.1 (0.9-1.3) | ||||
| Van den Eeden et al. 1990 | Case-control | United States | 3,284 cases 4,500 controls | Nonsmokers | 1.0 |
| Smokers | |||||
| Any birth defect | 1.0 (0.9-1.1) | ||||
From: Chapter 3. Health Consequences of Tobacco Use Among Women
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