First Babies from Cryopreserved Oocytes in Hungary

Embryo cryopreservation (CP) is a well established technique and it has been widely used for years with good results on the field of human assisted reproduction. Oocyte CP offers more advantages compared with embryo freezing with regarding ethical, legal …

First Babies from Cryopreserved Oocytes in Hungary

Objective To evaluate the value of oocyte cryopreservation (CP) in our clinical ICSI program. Methods Freezing procedure with medium containing 1.5 mol/L propanediol (PrOH) 0.3 mol/L succrose and traditional slow-freezing protocol were used. Thawed oocytes were fertilized with ICSI (4-6 h after thawing),and fertilization was assessed 12-16 h later. Laser assisted hatching was performed on all transferred embryos and embryo transfer was carried out 48-72 h after ICSI. Results Eighty-five eggs were thawed and survival rate of 75.3% (64/85) was obtained. Sixty-four oocytes were inseminated with ICSI,47 fertilized (47/64; 73.4%) and a cleavage rate of 85% (40/47) was obtained. Embryo transfers were performed in 18 patients,and 4 (19%) resulted in clinical pregnancies. One of the pregnancies encountered first trimester abortion. Implantation rate were 17.2% (5/29) per embryo and 5.8% (5/85) per egg thawed. In all cases,chorion biopsy was performed resulting 46 XY kariotype. Conclusion Our results provide further evidence of that although egg freezing cannot currently claim to be a routine procedure in human IVF,there will certainly be a place for oocyte CP in reproductive medicine in the future.