Table 7.
Risk of childhood cancer according to the trimester of prenatal diagnostic x-ray exposure based on medical records: Oxford Survey of Childhood Cancer case-control study.
| Trimester of Exposure | Fetal Age in Weeks | No. Cases / No. Controls | Odds Ratiosa |
|---|---|---|---|
| First trimester | 0 - 13 | 51 / 16 | 2.7 |
| Second trimester | 14 - 26 | 75 / 58 | 0.9 |
| Third trimester | 27 - 40 | 1317 / 1014 | 1.0 |
Source: Gilman et al. 1988 [128]
a
Adjusted for sex, birth year, social class, maternal age, birth order, exposure-age or film number (e.g., average number of films was higher for the first trimester than for later diagnostic x-ray assessment)