<unk>  is useful for leftover embryos after a cycle of in vitro fertilisation, as patients who fail to conceive may become pregnant using such embryos without having to go through a full IVF cycle. Or, if pregnancy occurred, they could return later for another pregnancy. Spare oocytes or embryos resulting from fertility treatments may be used for oocyte donation or embryo donation to another woman or couple, and embryos may be created, frozen and stored specifically for transfer and donation by using donor eggs and sperm.
Embryo cryopreservation
Fetal surgery
Egg donation
Embryo transfer
Semen cryopreservation
Ovarian tissue cryopreservation
Assisted reproductive technology
In vitro fertilisation