Endocrine Abstracts

A wide range of reproductive functions are susceptible to adverse affects from cancer treatment. Effects on spermatogenesis are more common than deficiencies in testosterone production, but in the female the gametogenic and steroidogenic aspects of gonadal function are more intimately associated. Radiotherapy can compromise hypothalamic and pituitary function, the ability of the uterus to support a pregnancy, and erectile function. Alkylating agents are regarded as having highest gonadatoxicity and age is an important factor in women. Ovarian failure is readily detectable, but there is increasing interest in detection of subclinical loss of follicles and prediction of the loss of reproductive lifespan. Anti-Müllerian hormone is promising in this regard. Sperm cryopreservation has established benefit but is variably available and strategies to preserve female fertility are developing rapidly. There is increasing observational data that GnRH analogues may be protective but RCT-based confirmation is lacking. Options include ‘emergency’ IVF with embryo or oocyte cryopreservation: the former is an established technique but requires time, money and male involvement. Oocyte cryostorage is more experimental and also generally involves ovarian stimulation which may be undesirable in hormone dependent diseases. Ovarian tissue cryostorage has now resulted in a small number of successful pregnancies and has the potential for application to girls but is invasive, and no options exist for prepubertal boys. The generation of germ cells from embryonic stem cells raises the possibility of artificial gametes. These issues are all of increasing importance because of steadily rising survival rates particularly among children.