Human oocyte cryopreservation

Subfertility in children and young people treated for solid and haematological malignancies

Children treated for cancer may exhibit impaired fertility in later life. A number of chemotherapeutic agents have been identified as being gonadotoxic, and certain treatment regimens are particularly associated with subsequent infertility. Radiotherapy can also cause gonadal damage, most notably after direct testicular or pelvic irradiation or following total body irradiation. Because of the varied nature of the cytotoxic insult, it can be difficult to predict the likelihood of infertility in later life. Currently, cryopreservation of spermatozoa, oocytes or embryos is the only method of preserving fertility in patients receiving gonadotoxic therapy. This is only applicable to postpubertal patients and can be problematic in the adolescent age group. At present there is no provision for the prepubertal child, although there are a number of experimental methods being investigated. However, in addition to the many scientific and technical issues to be overcome before clinical application of such techniques, a number of ethical and legal issues must also be addressed to ensure a safe and realistic prospect for future fertility in these patients.

Liver Transplantation Using Liver Grafts Preserved Under High Pressure

To extend organ preservation time, we attempted to establish a unique method of maintaining a preservation solution in a stable unfrozen state below its freezing point by pressurizing the solution. Livers removed from Lewis rats (RT1l) were stored in UW solution pressurized at the prescribed pressure. After the termination of preservation, orthotopic liver transplantation was performed. Experiment 1: Liver grafts were pressurized up to 30, 40, 50, and 70 MPa and preserved at 0 degrees C for 60 min. Experiment 2: Liver grafts were compressed at a rate of 1.32 or 0.04 MPa/s to 35 MPa and preserved for 60 min at 0 degrees C. Experiments 3 and 4: Liver grafts were pressurized up to 5, 10, 20, and 30 MPa and preserved at -2 degrees C (Exp. 3), -3 degrees C or -4 degrees C (Exp. 4) for 5 h. All rats transplanted with livers pressurized up to 30 MPa (Exp. 1), all rats in the 5 MPa and control groups at -2 degrees C (Exp. 3), and all rats in the 5 MPa group at -3 degrees C (Exp. 4) survived for 2 weeks. In light microscopy, diffuse hemorrhage and vacuolar degeneration of hepatocytes were observed in a pressure-dependent manner. Liver grafts preserved under pressurized, subzero nonfrozen condition have sufficient function to sustain the life of rats after orthotopic transplantation.

The effect of cytotoxic chemotherapy on female fertility

Nurses are now primarily responsible for the provision of patient information, and the administration of an escalating number of cytotoxic agents. This paper aims to provide nurses with key information concerning the adverse effects of cytotoxic chemotherapy on the reproductive system of women of childbearing age. The provision of information on gonadal function and fertility is vital, particularly with the increase in the survival of women treated for cancer, and the trend towards women starting a family later in life. Gonadal toxicity of the various cytotoxic agents, disruption of the menstrual cycle, premature menopause, avoidance of pregnancy, chemotherapy in pregnancy, and fertility prospects post-chemotherapy are addressed in this paper.

Posthumous reproduction: current and future status

Posthumous reproduction became possible with the technologies of sperm cryopreservation and ART. The legal and social status of children born as a result of these technologies continue to evolve. The proper disposition of unwanted stored gametes and embryos remains unknown. Physicians are increasingly asked to make quick judgments on posthumous gamete retrieval. The procedures for gamete harvest are technically simple; however, one must carefully select cases with definitive prior intent to have children. There is a need for standardized legal protocols to protect the physician and the patient. The physician must use sound judgment and comply with accepted standards, when present, before performing any service for posthumous sperm retrieval and reproduction.