Cryopreservation

Oocyte (Egg) Cryopreservation Program gives women the possibility to store eggs at a younger age for use in the future when they are older. Oocyte freezing can be also used as a medical emergency in the setting of a newly-diagnosed cancer or for personal social reasons.

The technology holds great promise for women of reproductive age. The process involves and begins with ovarian stimulation, then oocyte or egg collection and vitrification procedure, storage in liquid nitrogen at -196° C, and for use at a later date.

Oocyte quality is best when a woman is in her reproductive prime (age 16 to 28). Many eggs are usually still of good quality in the mid-reproductive years (age 29 to 38) and may remain usable (but with diminished chance for producing pregnancy) in the late-reproductive period (age 39 to 44). It is crucial to have eggs frozen when they are of the best quality possible.

Victory IVF Unit has a staff dedicated and skilled to perform egg freezing program to assure patients are properly cared for, counseled and supported. We know this is a big decision for many women and we want to make the process as delightful and satisfactory as possible.

At Victory IVF we use a cryopreservation technique known as “Vitrification”. Vitrification involves ultra rapid freezing of the oocyte from 37 ºC to -196 ºC at a rate of more than 20,000 ºC per minute. High concentrations of cryoprotectants and high cooling rates are necessary to prevent cryoinjury and preserve the oocyte cell. Subsequent to the vitrification, the oocyte is stored in liquid nitrogen until they are needed. The eggs may be kept frozen indefinitely so it is crucial that patients maintain annual contact with the clinic so we know the eggs have not been abandoned.

When the patient decides they are ready to use their eggs, they will be thawed in the laboratory. The thawing process is rapid and is carried on the same day the eggs will be fertilized and must be synchronized with a woman’s cycle. Over 90% of frozen eggs, on average, survive the freeze-thaw procedure.

Thawed eggs are next fertilized in our laboratory using a technique called Intra-Cytoplasmic Sperm Injection (ICSI). A single sperm is injected into the centre of each oocyte. On average, about 60% – 70% of the injected eggs will be expected to fertilize normally.

After fertilization, the oocytes, now called embryos, will be cultured in the laboratory for 2 to 3 days, growing and dividing. Take note that not all fertilized eggs will divide to make nice embryos. Those that do survive and progress are again related to a woman’s age.

Prior to transfer, your doctor will discuss with you the number of embryos recommended for transfer. Your doctor will transfer the fertilized eggs (embryos) into the uterus using a small catheter and are visualized under an abdominal ultrasound.

The following women may benefit from this procedure:

• Patients at risk of premature menopause and ovarian failure
• Oocyte Banking for donation programs
• Fertility Preservation: Women undergoing chemotherapy or radiotherapy to treat cancer
• Women who do not have a male partner or prefer not to use sperm from a partner or donor
• Women that are in a career or are not yet in a stable relationship
• Cases with no sperm available at the time of egg collection
• Patients who prefer to cryopreserve oocytes instead of embryos for religious reasons.