The fate of cryopreserved human embryos approaching their legal limit of storage within a West Australian in-vitro fertilization clinic.

Human embryos can only be stored in the first instance for 3 years in Western Australia, according to the West Australian Reproductive Technology Act. Thereafter, an application must be made to the local regulatory body, the Reproductive Technology Council, for an extension. Of the 650 batches of embryos frozen between 8 April 1993 and 31 October 1995, 170 (26.2%) batches were still in storage after 2.5 years. A reminding letter was sent at this time to the couples to whom the embryos belonged, i.e. 6 months before the expiry of the initial storage period, asking for clarification of what was to be done with the embryos. A large proportion of patients (64.7%) chose to either extend the storage period or thaw and transfer the embryos. Curiously, more batches of embryos were discarded (18.8%) than donated to other couples (5.9%). Contact with the patients was lost in a small but significant proportion of cases; more of these had been unsuccessful in their treatment (20.4%) than had achieved a pregnancy (4.3%).