Oocyte Cryopreservation: New Era in Gaining Time in Having Child
The place of women in social life has changed over the years and the education process has been prolonged and career has become important for the woman. Women who try to walk in parallel with men in business life try to postpone having marriage or children mostly during this time period. However, the biological watch works against women, and over the years, the ovarian reserve decreases, and the quality of the decreasing eggs deteriorates.
In addition to social reasons, the ovarian reserve may decrease spontaneously or due to medical necessity at an early age.
In the presence of early menopause in the family, the menstrual pattern of the woman should be questioned well and hormone tests should be performed in irregularities. The genetic aspect of the ovarian reserve cannot be denied, although it is not an absolute rule. The woman who already has the chance to know her family history generally applies by emphasizing this point in a high awareness.
There may be surgical procedures regarding the ovaries or situations that require removal of the ovaries. Radiotherapy and chemotherapy will decrease the ovarian reserve in women who are planning cancer treatment. Before all these initiatives, a future plan is necessary to protect fertility.
Egg freezing was legally possible only in patients who received cancer treatment in the past years. Since November 2015, the laws in our country legally give the right to store eggs in women whose ovarian reserves are decreasing or if they have no risk of early menopause. For this, the requirement, which is proven by tests, is signed by three specialist doctors, and a report can be created and the egg can be stored.
How does the process go?
The patient, who was previously interviewed and informed, whose examination was completed and the tests were prepared, is seen on the 2nd day of menstruation and an appropriate dose of gonadotropin is started. Ovulation induction, which is the first stage of the IVF program, is started and daily injections are planned for the patient, followed by ultrasonography every 2-3 days. After 12-15 days of follow-up, the eggs are collected under anaesthesia and with ultrasonography when they reach a certain size. After this procedure, which lasts for 15-20 minutes, the patient is rested for 1-2 hours and sent home after the control. Among the eggs collected, mature and healthy ones are frozen in the embryology laboratory by vitrification technique. The egg cell is the largest in the human body and contains a high amount of fluid. Fast freezing process with vitrification method will prevent liquid crystals from forming while freezing. Frozen eggs are stored in liquid nitrogen tanks at -196 degrees.
Storage technique: Fast freezing with vitrification!
The most important detail in egg storage is laboratory quality. Laboratories that use the vitrification technique correctly, renew their technology and work with experienced embryologists should be preferred. Fast defrosting is as important as fast freezing. It should not be forgotten how valuable the egg cells stored with hope in the patient, whose chance of having a child is limited, and when it is resolved again, the chance of success as much as the experiment in the fresh cycle should be provided.
How many eggs, for how long?
The more the number of frozen eggs, the greater the chances of the woman. In women under 35, the pregnancy rate per egg is 4% and it is recommended to keep at least 7-10 eggs. In women over 40, the pregnancy rate per egg decreases to 1% and the number of eggs stored should be very high considering this rate. There is no storage time limit for frozen eggs. If the eggs are frozen in groups, a separate test tube baby can be applied for each group that is thawed.
At what age can the procedure be done?
The most important parameter that changes the success of the treatment in IVF procedures using frozen eggs is the age at which the woman hides her eggs. Eggs can be stored at any age, but the ideal is to keep as many eggs as early as possible. The earlier it is stored, the better the egg quality will be. In this case, if the health condition permits, the woman can have children at the desired age. Anomaly risks for the baby will be equivalent to the risks of age stored eggs. While the success rate is quite high with the eggs stored before the age of 35, the success rate decreases as the age increases. However, for many social reasons, eggs may be stored at any age.