Spare embryos from your IVF treatment can be frozen for future use, depending on their quality. Embryos can be stored for up to ten years for future treatment if your first cycle was unsuccessful or for siblings. Freezing is complex and you should bear in mind that success rates can be reduced with frrozen embryo transfer.
A frozen embryo transfer can be performed in either stimulated or unstimulated cycles. During an unstimulated natural cycle, the embryo(s) are replaced when implantation is most likely.
With a stimulated cycle, you will need to take medication to go through the process of down-regulation. This temporarily shuts down your ovaries and prevents any eggs from being released. You will have a scan on day two or three of your period and start taking medication to prepare your womb for the embryo transfer. A second ultrasound scan at day eight or nine will be performed to check the thickness of your endometrium. Once it is of the appropriate thickness we can start the embryo thawing process and book your transfer.
Our embryology team will inform you of how well your embryos have survived the thawing process and if they are of good enough quality for your transfer to take place. Sometimes embryos do not survive the thawing process. If this happens, we will book you a review appointment with one of our specialists to discuss your options going forward.
The embryo transfer is similar to a smear test. It may cause some minimal discomfort. The culture medium containing one or two embryos is loaded into a thin catheter with a syringe on the end. The doctor carefully guides the catheter through the vagina and cervix, and deposits the embryo(s) into the uterus. Implantation begins three to four days later.