Benefits and concerns of an embryo cryopreservation programme

Following fresh embryo transfer in a stimulated IVF cycle, supernumerary embryos suitable for cryopreservation are available in a large number of cycles. In a routine IVF practice, 60% of stimulated in vitro fertilization (IVF) cycles may yield surplus embryos suitable for cryopreservation. Successful cryopreservation of zygotes and embryos has greatly enhanced the clinical benefits and cumulative conception rate possible for a couple following a single cycle of ovarian stimulation and IVF. Other clear benefits include the possibility of avoiding fresh embryo transfer in stimulated cycles with a potential for ovarian hyperstimulation syndrome, or in which factors that may jeopardize implantation are apparent (e.g. bleeding, unfavourable endometrium, polyps or extremely difficult embryo transfer).

However, a unit that offers embryo cryopreservation must also be aware of logistic, legal, moral and ethical problems which can arise, and ensure that all patients are fully informed and counselled. Both partners must sign comprehensive consent forms which indicate how long the embryos are to be stored, and define legal ownership in case of divorce or separation, death of one of the partners, or loss of contact between the Unit and the couple. At Bourn Hall Clinic, all couples with cryopreserved embryos in storage are contacted annually, and asked to return a signed form indicating whether they wish to

1. Continue storage

2. Return for frozen embryo transfer

3. Donate their embryos for research projects approved by the independent Ethics Committee and the Human Fertilization and Embryology Authority (HFEA)

4. Donate their embryos for ‘adoption’ by another infertile couple

5. Have the embryos thawed and disposed of.