EGG DEVELOPMENT

Under normal conditions, one egg develops in a woman’s ovary per month. The aim of IVF is to obtain more than one egg. For this purpose, hormonal drugs that stimulate the ovaries are used. In IVF, the treatment plan to be applied is decided according to the number of eggs in the ovaries and hormone levels on the 3rd day of the menstrual period. Accordingly, the treatment is started on the 21st day of the menstrual period or during menstruation. She is called for check-ups at certain intervals and follicle development is checked. When at least 3 follicles reach 17-18 mm, an injection of 10,000 units of HCG (human chorionic gonadotropin), commonly known as the cracking needle, is administered. At this time, the thickness of the endometrium should also be at least 7 mm. Egg collection is performed 34-36 hours after the cracking needle.

Collecting Eggs

Eggs that are grown with drug treatments that start on the 2nd day of menstruation are collected from the ovaries with a special device under anesthesia in the operating room environment. The collected eggs are first placed in special culture solutions, then kept in incubators containing 6% CO2 at 37 degrees for 3-5 hours. During this process, the sperm sample taken from the man is washed and prepared. The eggs are fertilized with sperm using a microinjection technique with the help of a special microscope. After 14-16 hours, the cells around the eggs are cleaned and fertilization is checked. The patient does not feel any pain during this procedure.

Development of Eggs and Embryo Development

During the microinjection process, the collected eggs are incubated in incubators containing 37 degrees and 6% CO2 for 2-3 hours in culture solutions to complete their maturation. During this time, a semen sample is prepared. After 2-3 hours, the cells around the eggs are cleaned and their maturity is checked. Only mature eggs should be processed. After the eggs are cleaned, the microinjection process is performed.

Embryo Quality

The quality of the embryos is evaluated according to some shape (morphological) parameters after fertilization. The morphology of the embryos is evaluated under a microscope and according to the following criteria.

Embryo cell (blastomere) count

Embryo blastomere size (equal or unequal blastomeres)

Presence and percentage of fragmentation (non-viable cell debris) In the light of all these criteria, embryos are classified according to their quality (grade) as follows:

Grade I embryos: These embryos have equal-sized, regular blastomeres and no fragments.

Grade II embryo: Contains blastomeres of equal size but contains a small amount of fragments (<20%).

Grade III embryo: Blastomeres are unequal and fragments are abundant. (20%-50%)

Grade IV embryo: Blastomeres are unequal and fragments are more than 50%. Studies have shown that the chance of pregnancy is higher with the transfer of Grade I and Grade II embryos than with the transfer of Grade III and Grade IV embryos due to the higher developmental potential of these embryos.

Embryo Freezing

Frozen embryos are stored in liquid nitrogen (-196 degrees) until they are used again. The main indications for embryo freezing are:

There are still a large number of quality embryos left after transfer.

Any problems that arise in the woman during the period when the embryos are to be transferred (for example, overstimulation of the ovaries during hormone therapy)

The endometrium is of a thickness that is not suitable for pregnancy.

TESE (Obtaining Sperm from Testicular Biopsy)

In cases where there are no sperm cells in the semen or at least 80% of them are dead, sperm cells can be obtained from the testicular tissue (ovaries) and microinjection can be performed. These procedures, which are performed with local anesthesia, have no negative effects on male sexual health. In cases of azoospermia (no sperm), chromosome analysis should be performed before the procedure for patients who will undergo tese or micro tese.

MESA (Micro-Epididymal Sperm Aspiration)

In the MESA procedure, sperm is obtained from the sperm ducts of patients with blocked ducts through a microsurgical procedure. Microinjection is applied with the obtained sperm.