Table 4.

Risk for Spontaneous Abortion by Estimated Level of Irradiation to the Ovary and Uterus and Pituitary Gland Among Survivors of Childhood Cancer, With Sisters As Referent

Level of Irradiation		No. of Women Who Became Pregnant	No. of Pregnancies	Spontaneous Abortions		PR*	95% CI
Ovary and Uterus	Pituitary Gland			No. of Abortions	No. of Women
Low†	Low†	59	152	7	6	0.8	0.3 to 1.7
Low†	High‡	60	137	15	13§	1.8	1.1 to 3.0
High‡	Low†	35	86	14	11‖	2.8	1.7 to 4.7

Abbreviation: PR, proportion ratio.

^*Adjusted for age of mother at pregnancy (linear spline) and calendar time (linear).

^†Includes dose category “low or medium.”

^‡Includes dose category “medium or high.”

^§Eight survivors of CNS tumors, three of leukemia, and two of retinoblastoma.

^‖Seven survivors of Wilms’ tumors, two of soft-tissue sarcomas, one of malignant lymphoma, and one of gonadal tumor.