Oocyte cryopreservation is a suitable fertility preservation option for women who are not partnered, have ethical objections to cryopreserving embryos or wish to have complete reproductive autonomy. There are several reasons a woman might choose to cryopreserve eggs such as:
- To preserve fertility before cancer treatment,
- To preserve fertility before starting medications that negatively impact ovarian function, or
- To provide a higher chance of pregnancy in the event she does not want to have a baby until she is older.
In this procedure, injectable fertility drugs (called gonadotropins) are used to stimulate the ovaries to recruit and mature multiple follicles that each contain an oocyte (egg). Most women will take these drugs for 8 to 12 days. During this time, she is asked to come in several times for monitoring, which includes an ultrasound and bloodwork to assess how she is responding to the fertility drugs. Once she has enough follicles that are large enough to produce a mature egg, she is given a trigger drug to mature the eggs and 36 hours later, the eggs are retrieved through a simple outpatient procedure called transvaginal oocyte retrieval.
The retrieval takes about 30 minutes and the woman is under anesthesia. The oocytes that are obtained are then cryopreserved (they are not fertilized) and stored in liquid nitrogen. The entire process takes approximately two weeks. At a later date, when the woman wants to conceive, the oocytes can then be warmed and fertilized using a partner’s or donor’s sperm. Oocytes maintain viability even after decades in cryostorage, if properly maintained.
With improvements in egg freezing over the last ten years, oocyte freezing is no longer seen as an experimental procedure. Success rates (the rates of having a live birth) are largely dependent on the age at which a woman freezes her eggs, with younger women having higher rates of success than older women. If you have considered egg banking, please schedule a consultation with a Baylor Medicine reproductive endocrinology and infertility specialist, who would be happy to talk through the process as you decide if it is right for you.
For more information or to schedule an appointment, call the Family Fertility Center at (832) 826-7272.