Fertility and offspring

Treatment of paediatric cancers can affect the endocrine system (hormone production) and fertility. Investigations are also underway on the effects of treatments on children (offspring) of people treated for paediatric cancer.


Hormone production and fertility

Several glands are involved in the production of sex hormones and thus affect fertility:
– Gonads (ovaries for girls and testes for boys)
– The hypothalamus and the pituitary, located in the brain, which stimulate or inhibit the gonads.
Gonadal failure (testicular or ovarian) covers not only fertility but also overall hormonal function: lack of puberty, disorders of feminisation and masculinisation. Disorders of feminisation and masculinisation can be corrected by life-long hormone therapy.

Radiotherapy: Irradiation of the pituitary gland or hypothalamus can be responsible for gonadal failure. For a long time, it has been known that exposure of the ovaries or testes to radiation is associated with a risk of permanent gonadal failure. Therefore radiation therapists are trying to avoid irradiating these organs during treatment, except in the case of total body irradiation. Radiation to the abdomen, including low dose radiation therapy, can result in menopause (end of period fertility of women), which is called early menopause before age 50 (the average age of menopause in the general population).

Chemotherapy: After chemotherapy, the risks are mainly related to a class of drugs called alkylating agents. These drugs are often given in high doses before bone marrow transplant or peripheral stem cells (autologous or allogeneic).
– In men, alkylating agents given in a « conventional » way (non-autologous) can result in fertility problems by reducing the number or mobility of sperm (but not masculinity). Nevertheless, fertility can sometimes come back, years after treatment.
– In women, alkylating agents given conventionally (without autograft) can often result in a decrease in fertility (early menopause). The arrival of menopause is advanced by four years on average after the administration of alkylating agents. Alkylating agents given in high doses before autologous transplants pose a risk of global gonadal failure.
Oophorectomy or hysterectomy: if treatment includes surgical removal of an ovary, menopause is advanced by an average of seven years, whether or not the treatment includes alkylating agents or radiotherapy.

Sources
Results of the study FCCSS on endocrine effects of treatments for women, in particular on the role of chemotherapy, radiotherapy and oophorectomy: Publications