Cryopreserved blastocysts have a lower implantation but an equal live birth rate as compared to fresh blastocysts of the same quality - a case-control study.
The purpose of this case-control study was to compare implantation, pregnancy, and live birth rate of cryopreserved embryos with that of fresh embryos. A total of 1,488 assisted reproductive technology (ART) trials including 188 cryopreserved embryo replacement trials were reviewed. After proofing the exclusion criteria, 112 patients undergoing a cryopreserved embryo replacement (study group) were matched with 112 patients undergoing a fresh embryo transfer (control group). Matching was done for age of patients, number, and quality of embryos (Day 5 embryos). Data concerning maternal characteristics, survival rate of warming procedure, implantation, pregnancy, ongoing pregnancy, and live birth rates were collected. A lower implantation rate was found for cryopreserved embryo replacement compared to transferring fresh embryos. Live birth rate was found to be equal in both groups.
Shebl
Omar
O
IVF-Unit, Landes Frauen- und Kinderklinik Linz, Linz, Austria. omar.shebl@gespag.at
Ebner
Thomas
T
Sommergruber
Michael
M
Sir
Andreas
A
Tews
Gernot
G
D000328:Adult; D001755:Blastocyst; D016022:Case-Control Studies; D015331:Cohort Studies; D015925:Cryopreservation; D010064:Embryo Implantation; D004624:Embryo Transfer; D005260:Female; D006801:Humans; D050498:Live Birth; D011247:Pregnancy; D013997:Time Factors