Medical aspects
Extracorporeal fertilization is in vitro fertilization (IVF) of oocyte with the following cultivation and transplantation (transfer) of embryo to uterus.
The process of examination and treatment in the cycle of IVF lasts for 1,5-2 months till the statement of fact of pregnancy or its absence. During the process of examination prior to IVF Intended mothers and Surrogates undergo Ultra Sound testing, hormonal analyses of blood; tests on AIDS, hepatitis, syphilis; men undergo spermogram. In the case of necessity genetic analyses are conducted.
The first stage of in vitro fertilization is stimulation of ovulation. After medical examination hormonal medicines, which stimulate maturation of more than two oocytes, are prescribed for woman. It increases considerably the possibility of oocyte retrieval and fertilization. Moreover, it is noted that, when several fertilized oocytes are implanted, pregnancy begins more often and only one embryo develops which means, that some extra embryos are required for application of IVF. Duration of introduction of hormonal medicines with the purpose of stimulation of ovulation usually lasts fortnight. Nowadays recombinant medicines, obtained through genetic engineering, are used; they have advantages over the previous medicines, obtained from women’s urine during the menopausal period. Those medicines were causing allergic reaction, when applying some infectious complications are possible.
Complications of this stage of extracorporeal fertilization can consist in Ovarian hyperstimulation syndrome. It may manifests in stomach pain, abnormal bloating. With in time diagnostics, this syndrome can be treated and shall not have an influence on possible pregnancy.
At a certain amount and size of follicles of the inner layer of uterus, hormone level of blood, the next stage of IVF – puncture of follicles and retrieval of oocytes – is initiated. This small procedure is held in the outpatient setting during one day. It is the only procedure of IVF that requires use of anesthesia (short-term endovenous one). Puncture of ovary is performed by a needle through vagina under control of ultrasound; several oocytes are obtained as a result of this procedure. There are no complications after this procedure.
Sperm-oocyte fusion is performed by doctors-embryologists in a special laboratory. After 2-4 days embryos are prepared for transfer to uterus, embryo transfer is the easiest and painless procedure which is carried out with help of a special catheter. After this procedure woman should avoid physical activity and emotional stresses. Remaining embryos should be cryopreserved (frozen), oocytes and spermatozoids can be preserved too. In the case of failure attempt of IVF application previously obtained genetic material can be used next time.
After implantation of an embryo, certain medicines are transferred into a cavity of uterus. They assist pregnancy and prevent oocyte from rejection. This procedure is conducted until the confirmation of pregnancy, and in case of failure till the next menstruation.
