WHAT IS EMBRYO FREEZING? AT WHICH STAGE IS IT DONE?

WHAT IS EMBRYO FREEZING? AT WHICH STAGE IS IT DONE?

Sometimes embryos may need to be frozen during IVF treatment.

Even though freezing is known as "resting the uterus" among the people, it is not actually done because of the need to rest the uterus.

It is performed to increase the chance of pregnancy and often to reduce the existing risk of OHSS, since the hormones that rise above normal do not create suitable conditions for embryo transfer.

For patients with 15 or more eggs collected, freezing all of the embryos and transferring them in the following months increases the chance of pregnancy and is safer for the patient.

Today, this clinical picture called OHSS, which sometimes disrupts the life-threatening body functions, is very rare due to the widespread use of embryo freezing.

 

Conditions requiring embryo freezing;

  • OHSS (Ovarian Hyperstimulation Syndrome) in the possibility of activation of the ovaries,
  • If PGD (Pre Genetic Diagnosis) is planned,
  • In situations requiring embryo pooling,
  • If there is a surgical procedure planned before embryo transfer, because of polyp, endometrial adhesion and thinness, septum hydrosalpinx, myoma, etc.
  • If freezing was performed to protect reproduction before oncological treatment
  • It is performed if pregnancy is not desired immediately for social reasons.

WHICH METHODS ARE USED FOR FROZEN EMBRYO TRANSFER?

During the first or second menstrual period after Embryo Freezing, follow-ups are made to prepare the uterus for the transfer of the embryo, then the embryo is transferred into the uterus.

Three types of preparations can be made for this purpose;

  • Natural Preparation
  • Preparation by stimulating ovulation with various drugs
  • Preparation with hormone administration

Natural (Natural) Preparation:

Without giving any medication, ultrasonography and hormone levels are checked, after the detection of ovulation, the embryo transfer is made by planning the appropriate environment where the embryo will hold into the uterus. The natural preparation process is appropriate. It is advantageous not to use hormonal drugs for patients who have regular menstruation and ovulation, and whose thickness of the endometrium increases normally.

It is a safe method with a better chance of pregnancy and less chance of miscarriage. For women with regular menstruation, an average of 20 days is sufficient for preliminary preparation.

 

Preparation by Stimulating Ovulation:

By stimulating ovulation with letrozole, uterine preparation can be made with hormones secreted by the natural egg.

It is preferred in patients where the use of hormones is risky, PCOS (Polycystic Ovary Syndrome) without natural ovulation, obesity thrombophilia risk and the use of hormones such as breast ca

It is followed like natural egg tracking. If ovulation is achieved, the results are becomes successful.

 

Preparation by Giving Hormone Drugs:

It is the oldest and most classic application. Starting from the 2nd day of menstruation, within a period of 20 days, the inner layer of the uterus is thickened with hormonal drugs containing estrogen and progesterone, and embryo transfer is applied.

It is the most preferred preparation method in patients whose uterine lining is thin due to intrauterine adhesion. The medication dose is increased accordingly to the response of the patient.