This chapter describes the strategies of monitoring and selecting ovarian stimulation protocols, all aiming at optimizing in vitro fertilization (IVF) outcomes. The aggregate of the history, physical exam, antral follicle count (AFC) and hormonal assays predicts a good or poor responder and should be the basis of designing an initial IVF protocol. Once an individual is deemed a good responder, the focus of stimulation is judicious administration of an initial gonadotropin dose to mitigate the risk of ovarian hyperstimulation syndrome (OHSS). Gonadotropin-releasing hormone (GnRH) antagonist protocols have been increasingly applied to good responders due to their added advantage of diminishing the risk of OHSS. The timing of human chorionic gonadotropin (hCG) injection should be individualized based on several factors, including follicle diameter, serum estradiol (E2) level, prior cycle response, and embryo quality within the context of the particular controlled ovarian hyperstimulation (COH) protocol.

Advances in assisted reproductive technology (ART) have created opportunities for preservation of the reproductive potential of young males with cancer. Semen cryopreservation is possible in most adolescents with cancer regardless of age or diagnosis. Awareness by physicians is even more essential when dealing with younger populations. Theoretically, testicular tissue from prepubertal boys facing gonadotoxic treatment could be banked for many years for spermatogonial stem cell transplantation. Male germline stem cells are the only cells in postnatal mammals that undergo self-renewal and transmit genes to subsequent generations, since all female germline stem cells cease their proliferation before birth. Future possible methods of restoring fertility might include the derivation of mature sperm cells from human embryonic stem cells. Embryoid bodies were shown to support maturation of the primordial germ cells into haploid male gametes, which when injected into oocytes round off the somatic diploid chromosome complement and develop into blastocysts.