Freeze-all technology
What is freeze-all technology?
A few years ago, in IVF, it was considered optimal to achieve synchronous maturation of several follicles, aspirating (egg retrieval - OPU) 10 to 12 oocytes, 70-80% of which are mature (at metaphase II-MII). With embryo development up to day 5, selection was performed in the embryology laboratory, as only competent embryos reached the blastocyst stage of development. At fresh embryo transfer (ET), one or two blastocysts were returned with a success rate of about 50% for clinical pregnancy rate (CPR). The remaining embryos were frozen, and FET (freeze ET) was performed later in the natural cycle with a success rate of 30-35% for CPR. The cumulative success rate was around 60%.
The simple conclusion then was that "more is not better" (more than 12/15 oocytes). It should be remembered that blastocyst ET is only an advantage for patients with a good prognosis.
What have new technologies brought us?
Freezing all embryos is now a common trend and a new, very successful IVF technology. The circumstances that drive the choice of all freezing procedures are:
CURRENT IVF/ICSI PROCEDURE (FRESH)
ADVANCED IVF CENTERS AND VITRIFICATION
DISEASE OR CONDITION OF SEXUAL ORGANS THAT WOULD REDUCE THE SUCCESS OF FRESH ET
RECEPTIVE ENDOMETRIUM
PRESERVATION OF PERSONAL FERTILITY
NEED AND POSSIBILITY OF EMBRYO BIOPSY
DONOR PROGRAMMES
BETTER IVF RESULTS (FET VS. FRESH)
Several extensive studies have shown that this technology provides better outcomes - OR 1.38 (OPR, CPR) and does not increase complications (spontaneous abortion) or congenital abnormalities in babies. All perinatal indicators are better with FET than with fresh ET pregnancies. Only the babies are heavier - big baby syndrome.
A new philosophy of better IVF/ICSI outcomes has been implemented alongside the new options. More aggressive ovulation stimulation (OS) is only allowed to an experienced human reproduction subspecialist with the knowledge and ability to apply the latest technology. Favourable cumulative success rates in younger women now range between 60-80% in LBR. It is clear that such a strategy is only applicable to potential patients.