What is Oocyte Freezing?
Today, oocyte freezing is among in vitro fertilization practices and it is possible to collect eggs of women and freeze and store them for possible future pregnancy requests.
As is the case with in vitro fertilization therapy, eggs – the largest cell of a body – are frozen under zero Celsius degrees and stored. Thus, reproductive age and characteristics of the mother at the date of the oocyte freezing are protected and accordingly, healthy pregnancies are intended.
How Is Oocyte Cryopreservation Performed?
For oocyte freezing, the candidate mother is started on a medication treatment for approximately 10 to 14 days after menstrual cycle ends and thus, ovaries are regularly stimulated. In this period of time, growth of eggs is monitored with ultrasound. Eggs are collected after they reach a certain size, placed in liquid nitrogen vessels and frozen at -196 ℃.
General anesthesia is administered for oocyte pick-up procedure. Therefore, patients are advised to avoid anticoagulant medications (drugs that inhibit coagulation of blood) on and after the surgery day. Antibiotics and painkillers can be used after the surgery. Patients need to rest for 1 to 2 hours.
Why are Oocytes Frozen and Who require this procedure?
- Oocytes are frozen, if the number of sperm obtained from man is low on the day of occyte pick-up.
- When oocytes are overstimulated, eggs can be frozen, as it is necessary to postpone the transfer.
- For patients with low number of oocytes, an egg bank can be organized with oocyte freezing to increase chance of pregnancy.
- Oocyte freezing is recommended for diseases that lead to ovarian deficiency or cancer patients before radiotherapy, chemotherapy or stem cell transfer.
- For women who are at advanced age, but do not plan pregnancy, reproductive capacity can be protected with oocyte freezing.
Frequently Asked Questions
What is age-related criteria for Oocyte Freezing?
Since ovarian reserve decreases over time in women older than 35, oocyte freezing is recommended for this age range.
How long does oocyte freezing take?
Considering the preparation for the procedure, oocyte freezing lasts for approximately 12-15 days.
Does oocyte freezing harm eggs?
Oocyte freezing intends to stop molecular structure and metabolic activities of the cell for a short period of time. In cryopreservation performed with up-to-date techniques, such as vitrification, formation of ice crystals that cause death of the cell is prevented and cells can be stored in liquid nitrogen without any loss of viability.
How Long Can Frozen Eggs Be Stored?
It is possible to store frozen eggs for 5 years. It can be extended, if required.
How is egg freezing performed in virgin women? Is virginity lost?
Oocyte pick-up is performed with vaginal approach. Therefore, it is evaluated whether hymen allows insertion of the ultrasound probe and the hymen is incised, if required. On the other hand, oocyte pick-up with abdominal approach is not advised due to risk of organ injury.