As the traditional slow freezing method would form ice crystals in the cooling process, destruct intracellular organelles and cell structure, resulting in cell damage. Therefore, vitrification rapid freezing method is born. This method is to freeze the cells in -196⁰C of liquid nitrogen (N2(l)) after adding the high concentrated frozen protecting liquid to make the cells in extremely sticky but no crystals vitrification status, significantly increasing the unfreezing survival rate of frozen cells.
According to figures, vitrification unfreezing survival rate is 98%, and that of traditional slow freezing is only 55%. Since 1980s, scientists had already successfully frozen embryos (among the successful IVF, 16% are done with the frozen embryos), but the freezing technology of ova is not so mature until only recently. As a single cell, the water content is very high inside the ovum, therefore, slow freezing method would ice crystallize the ovum and cause damage to ovum. Over the past ten years, more and more medical institutions provide ovum freezing service to the cancer patients with radiotherapy, but with poor success rate.
In 2006, embryos scholars developed a new freezing preservation method – after Vitrification, several peer-reviewed studies after a few years, including NYU Medical Center, have published a quite remarkable achievement. Dr. Hung-Chi Chang had also played a major role in NYU Medical Center Ovum Freezing Technology Professional R&D Team from 2001 to 2007.
Applicable Scope of Vitrification Technique
1.Reservation of rest embryos after impanation
As recommended by us for separate embryo implantation, and according to provisions stipulated in the Act on Artificial Procreation, in vitro fertilization embryo implantation, only a maximum of four at one time. If cultivate more than 4 good-quality embryos, redundant qualified embryos can be preserved with freezing technology.
2.Improve natural cycle/Mild stimulation IVF embryo implantation rate
According to statistics, implantation rate of freezing embryo implantation is higher than that of fresh embryo implantation. This is because if adopts ovulation inducing agent and other artificial hormones in order to obtain more qualified ova in the natural cycle, and results in insufficient endometrium thickness, the implantation rate is normally decreased. Vitrification technique can preserve the good qualified embryos in advance, and then carry out the implantation when uterus condition is in better cycle, so as to improve implantation success rate.
3.Solve the time matching problem between sperm extraction and egg retrieval
If the husband is unable to cooperate with sperm extraction in the egg retrieval day due to other business, the sperm extraction can be carried out in advance, which is to adopt freezing technology to preserve first and then unfreeze on egg retrieval day to carry out the vitro fertilization.
4.Reservation of donated ova and sperms
Owe to vitrification quick freezing technology, the survival rate of the unfrozen germ cell has significantly improved, therefore, donator and donee do not need to real-time cooperate and decrease the cooperation difficulty of donation.
5.Reservation of gold fertility
Patients after cancer treatment would temporarily loss fertility due to the side effects of anticancer drug and radiation therapy, which means that woman’s ovary would no longer ovulate and man’s testicles are no longer produce sperms, even some may be permanent infertility. In recent years, the improvement of cancer treatment technology has increased the survival rate, so the fertility preservation after the cancer treatment has gradually drawn patients’ attentions. At the same time, the rapid advancement in reproductive medicine technology also has brought cancer patients back to life after the treatment. Therefore, in addition to the married couple who can freeze and preserve embryos, the unmarried female can also free ova and unmarried male can free sperms. For whomever has own career planning or has to carry out special medical plan, Vitrification technique can provide you a future with hopes！