Embryo donation is one of the assisted reproduction techniques. The embryo is created by the fusion of donated egg with sperm of donor. A couple can choose between finding a suitable donor and use of donated embryos stored in cryobank. In the cryobank are preserved embryos which were created with assisted reproduction techniques in other couples. In the event of that the couples did not use all of their embryos, they could decide to freeze these embryos and offer it to other couples. Signed informed consent of both partners who provide their embryos is required for this method. Unfortunately there is no 100% certainty that the embryos will survive the thawing process. Percentile survival rate is high, ranging between 85% and 90%. Embryo donation is anonymous, and clients can choose the embryo according to characteristics of donors who donated the eggs and sperms. The aim is always to ensure that the donors will be most alike recipients. The second option is to choose separate donors. The donors are selected according to very strict standards in which health of the donor is taken into account. Tests for the genetic defects and infectious diseases such as HIV, syphilis and hepatitis B and C are performed. Selected eggs are fertilized with donated sperms in laboratory conditions. The results of both procedures are living embryos which are tested to ensure that there is no genetic defect. If the embryos are assessed as healthy, it may proceed to their insertion into the uterus. However, the condition is that both partners must be infertile because otherwise other method of assisted reproduction is recommended to them.
The birth of new life is fascinating but very complex process. In order to generate a new life, interplay of many systems of male and female body is necessary. A necessary condition for natural conception of child is that the sex cells of each partner had developed properly and also that the female body will be able to hormonally provide the conditions essential for development and growth of the embryo. In men, proper development of sperms in the testicular seminiferous tubules is the most important. The proper maturation and release of eggs during ovulation cycle, also tubal patency and uterine readiness for the adoption of fertilized eggs is essential for women. All these processes are controlled by a complex network of hormones which influence each other, and thus flawlessly control every step of maturation and release of both sperm and eggs.
If it comes to an error during the creation of a new life, reproductive disorders develop. There are many causes of infertility, from the genetic load of one or both partners, various diseases, hormonal disorders, disorders of the ovaries in which are the eggs formed, tubal blockage, anatomical abnormalities of the uterus, immune system disorders, disorders of sperm production, erectile and ejaculation dysfunction to bad lifestyle . Treatment of infertility depends on the underlying cause. If common treatment methods fail, it is accessed to the methods of assisted reproduction.
Conditions for donation of embryos
The donors and recipients must always undergo a thorough physical, genetic, endocrine and gynaecological examination. Testing for sexually transmitted diseases is also performed. Requirements for the donors are age 18-35 years, good health and quality of donated sample. Donation of embryos is strictly anonymous. Requirements for the recipient are maximal age of 47 year, good health state for pregnancy and negative HIV tests. All participants must sign an informed consent for the donation of embryos with the obligation to respect the anonymity.
The course of embryo donation
Systematic preparation of patient before the donation is necessary in order to proper nidation and survival of the embryo in the uterus. The lining of the uterus must be sufficiently grown for the proper nidation of embryo. Therefore, estrogens, i.e. sex hormones which will induce the growth of uterus lining, are given to patients. They are administrated in advance of 10-50 days. Just before the transfer of embryo into the uterus the patient begins to take progesterone. This is another hormone which function is to maintain the pregnancy. The implantation of embryo into the uterus is performed during so-called the implantation window. This is the time interval between 2nd and 6th day of progesterone administration. The patient must rest on cot after the implantation of embryo. The nidation of embryo is monitored by ultrasound and also by the level of pregnancy hormone, i.e. human chorionic gonadotropin (HCG).