Table 1.
Pregnancies, Pregnancy Outcomes, and Estimated PRs Among Childhood Cancer Survivors, Sisters, and a Population Comparison Group, With Sisters As Referent
| Study Group | Size of Cohort | Pregnancies | Fetuses* | Livebirths
|
All Abortions†
|
Stillbirths
|
|||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| No. | % | PR‡ | 95% CI | No. | % | PR‡ | 95% CI | No. | % | PR§ | 95% CI | ||||
| Survivors | 1,688 | 1,479 | 1,497 | 1,022 | 69.1 | 0.97 | 0.94 to 1.01 | 470 | 31.8 | 1.06 | 0.97 to 1.15 | 5 | 0.3 | 1.1 | 0.4 to 2.9 |
| Sisters | 2,737 | 5,092 | 5,139 | 3,574 | 70.2 | 1 | Referent | 1,548 | 30.4 | 1 | Referent | 17 | 0.3 | 1 | Referent |
| Population comparisons | 16,700 | 27,989 | 28,286 | 19,535 | 69.8 | 0.98 | 0.96 to 1.00 | 8,657 | 30.9 | 1.03 | 0.99 to 1.08 | 94 | 0.3 | 1.1 | 0.6 to 1.8 |
Abbreviation: PR, proportion ratio.
*
Multiple births were included in the analyses. For example, twins born alive were counted as one livebirth, whereas a twin who was stillborn would be counted as stillborn and the other as liveborn.
†
Including spontaneous abortions, induced abortions, ectopic pregnancies, hydatidiform moles, and other, primarily nonhydatidiform mole and missed abortions.
‡
Adjusted for age of mother at pregnancy (linear spline) and calendar time (linear).
§
Unadjusted estimate.