The goal at this initial and critical stage is to identify all factors preventing pregnancy. Both partners undergo detailed testing (ovarian reserve and uterine structure for women, sperm and genetic analysis for men). Once the underlying cause of infertility is found, the necessary preparatory steps and surgical procedures (e.g., hysteroscopy for uterine problems or micro-TESE to obtain sperm) are performed to increase the chances of pregnancy. Based on all this data, the most suitable IVF treatment protocol for the couple is determined and the implementation phase begins.

At this stage, the core procedures of the treatment—egg development and embryo creation—are performed. The woman is treated with hormone medications for 10–12 days to develop multiple eggs, and this process is closely monitored via ultrasound. The mature eggs are retrieved under anesthesia and fertilized with sperm (ICSI) in the laboratory to create embryos. The embryos are observed for 3 to 5 days, and the highest quality one is selected; assisted implantation is also performed during this process if necessary to support implantation.

In this final stage of treatment, the highest quality embryo or embryos selected in the laboratory are transferred painlessly into the mother’s uterus. Following this transfer, supportive medications such as progesterone are started to prepare the uterine lining and increase the embryo’s chances of implantation. The couple enters a critical period while waiting for the embryo to implant in the uterus. Approximately 10-12 days after the transfer, a beta-hCG blood test is performed to confirm pregnancy. If the test result is positive, regular pregnancy monitoring begins.