Table 2.
Pooled Risk of Childhood Acute Myeloid Leukemia Associated With Maternal Smoking Across Time Periods, Childhood Leukemia International Consortium, 1974–2012
| Window of Exposure | Total Controls, no. | Total Cases, no. | Exposed, % |
ORa | 95% CI | |
|---|---|---|---|---|---|---|
| Controls | Cases | |||||
| Ever-smoking | 5,929 | 563 | 42 | 42 | 1.01 | 0.84, 1.22 |
| Smoking during prenatal periodb | 12,631 | 1,266 | 29 | 26 | 0.93 | 0.81, 1.07 |
| Smoking during preconception periodb | 10,137 | 1,012 | 31 | 27 | 0.89 | 0.76, 1.04 |
| Smoking during pregnancyb | 12,621 | 1,266 | 19 | 15 | 0.95 | 0.81, 1.13 |
| Smoking after birth | 10,229 | 1,028 | 28 | 26 | 0.96 | 0.82, 1.12 |
Abbreviations: CI, confidence interval; OR, odds ratio.
a Odds ratios were adjusted for age, sex, ethnicity, highest parental education, and study center.
b Odds ratios were computed by using imputed values of education.