In recent years there has been an increased demand for fertility preservation.
Freezing and thawing sperm has very good survival rates for sperm mobility and sperm fertilization. Also, cryopreservation of sperm is not related to the development of congenital or other embryonic abnormalities. The sperm can remain cryopreserved theoretically indefinitely and used in future IVF efforts. In particular, scientifically pregnancy has been recorded using cryopreserved sperm of twenty years (20 years). Sperm freezing is recommended to:
· Adult men or teenagers who are about to undergo a cancer therapy (surgery, chemotherapy and radiation)
· Adult men or teenagers who are going to undergo any treatment that may affect their reproductive capacity
· Men to be subjected to surgery (prostate or testicular surgery)
· Men with exposure to chemicals, radiation or excessive heat that can cause infertility
· Male patients with previous medical history of oligoasthenospermia
Keeping fertility through egg freezing is one of the biggest gains in IVF, allowing thousands of women around the world to become mothers when they want it.
As a method, egg cryopreservation is addressed to women:
· Who want to prolong their fertility for the distant future for educational, professional, economic or purely personal reasons
· Who have a family history of premature menopause
· Who have health problems and are about to undergo treatments that cause damage to their ovaries and their eggs (ovarian ablation, chemotherapy or radiation therapy in cases of cancer)
The process of collecting eggs for cryopreservation is the same as for IVF after appropriate ovarian hormone stimulation. The eggs are then evaluated by the embryologists for their quality and maturity, prepared and frozen in liquid nitrogen containers (-196οC). When the woman wishes/can have a child, the eggs are thawed and fertilized in the laboratory and transferred to the womb as an embryos. When drug use is contraindicated, it is possible to collect eggs in a natural cycle or immature egg cells for women with polycystic ovaries.
The egg is the largest human cell and consists mainly of water and when it is cooled it forms crystals that can destroy it. With the vitrification method, however, it is achieved to freeze eggs with the highest survival rates to date. More specifically, vitrification is the rapid cooling process of eggs using a high concentration of cryoprotectant. The result is a glass-like cell, which is free of crystalline form. Approximately 95% of the eggs survive thawing, achieving fertilization rates, respectively, of fresh eggs.