The path to conceiving a child can be difficult and require the use of assisted reproductive technologies . In order for IVF to be successful, it is necessary to obtain several eggs. With natural ovulation, one, rarely two follicles ripen. And superovulation is a process when several mature in the ovary at the same time. It is created in the protocols of assisted reproductive technologies with the help of medicines. After receiving the eggs, they are fertilized and the embryos are transferred to the uterus.
Why do we need superovulation?
In in vitro fertilization, there is an IVF-EC protocol, or IVF in a natural (natural) cycle, when an egg is removed for fertilization during normal ovulation. This option is shown with a reduced ovarian reserve, when the number of immature follicles ends.
Indications for IVF-EC are also considered thrombophilia, antiphospholipid syndrome, habitual miscarriage, a history of oncopathology, contraindications to hormonal stimulation or poor quality of oocytes in response to it.
In IVF-EC, the frequency of pregnancy after embryo transfer is significantly lower, which is due both to the initial health conditions of the patients and to the peculiarity of the procedure – there is no possibility to choose an oocyte.
At the age of 40, according to world research, IVF EC is successful in 3-6% of cases, under 39 years of age, indicators vary in the spectrum of 11-53%.
Superovulation (ovarian stimulation protocol) allows you to achieve success much faster. With this phenomenon, 8-14 follicles mature in the ovary. And it’s not so much: some of them will be empty, some of them will be of poor quality. On average, 5-6 of the 10 follicles obtained during superovulation are selected for fertilization. The more oocytes, the higher the probability of success.
How is it stimulated?
To stimulate the maturation of a dozen follicles at once, hormonal drugs are used. They temporarily suppress their own hormones – luteinizing and follicle–stimulating (LH and FSH) and artificially stimulate the growth and maturation of follicles in the ovaries – with almost the same hormones created with the help of genetic engineering. Why do they do this?
The process of suppressing the production of the patient’s own hormones is necessary to control ovulation, otherwise there will be no eggs in part of the follicles at the puncture stage. In the natural cycle, the peak of LH production, the instigator of ovulation, occurs spontaneously. And without control over it, the eggs may not be in the follicles, but already outside – it will not be possible to get them from where.
At the final stage of maturation of oocytes, hCG hormone is injected, which affects the same way as luteinizing. This is how they achieve simultaneous and complete maturation of cells and their readiness for fertilization. As a rule, the injection of chorionic gonadotropin is carried out in the afternoon and after 36 hours a puncture with egg collection is prescribed.