About two thirds of patients treated for childhood cancer in Britain survive at least five years, and over 90% of these survivors are probably cured.1 Some survivors become infertile as a result of treatment, but many go on to have children.2 Adverse outcomes of pregnancy or impaired health of the children might in theory be related to constitutional genetic abnormalities in survivors associated with their cancer or to germ cell mutagenesis from radiotherapy or cytotoxic drugs. Treatment may also result in dysfunction of reproductive organs adversely affecting pregnancy outcomes or offspring. Adverse outcomes include increased risks of miscarriage, stillbirth, low birth weight, congenital malformation, cancer, and early death.

Survivors of cancer occurring in childhood or early adult life form one of the largest groups of people exposed to high doses of mutagenic agents before reproducing. Radiation dosimetry and cytotoxic drug doses are obtainable from detailed clinical records (although the retention of such records in the future is under threat in Britain). …