Embryo quality before and after slow freezing: Viability, implantation and pregnancy rates in 627 single frozen-thawed embryo replacement cycles following failure of fresh transfer.
Frozen embryo transfer cycles are now common practice, however, various aspects regarding the potential of frozen embryos remain unclear. The main goal of the present study was to assess embryo quality before and after slow freezing procedure, and more specifically blastomere loss and embryo quality as indicator of viability. A single center retrospective analysis of single frozen-thawed embryo replacements (s-FER) was performed. The embryo quality before and after slow freezing and thawing, implantation, and pregnancy rates were recorded. One hundred and twenty seven s-FER were included in the final analysis. The probability of achieving an ongoing pregnancy was significantly associated with embryo quality and the percentage of blastomere loss after thawing. Considering thawed embryos, a non-significant difference in term of implantation rate was observed, regardless to their post-thawing quality and the percentage of blastomeres loss. In conclusion, current data suggest that thawed embryos are capable of implantation regardless of their morphological quality and the degree of cryoinjury sustained.
Center of Reproductive Medicine and Surgery, Arcispedale Santa Maria Nuova (ASMN) - Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS), Reggio Emilia, Italy.
Francesco
F
Capodanno
Center of Reproductive Medicine and Surgery, Arcispedale Santa Maria Nuova (ASMN) - Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS), Reggio Emilia, Italy.
Gaetano
G
De Feo
Department of Woman and Child Health, University of Padua, Padua, Italy.
Salvatore
S
Gizzo
Center of Reproductive Medicine and Surgery, Arcispedale Santa Maria Nuova (ASMN) - Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS), Reggio Emilia, Italy.
Alessia
A
Nicoli
Center of Reproductive Medicine and Surgery, Arcispedale Santa Maria Nuova (ASMN) - Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS), Reggio Emilia, Italy. Electronic address: stefanopalomba@tin.it.
Stefano
S
Palomba
Center of Reproductive Medicine and Surgery, Arcispedale Santa Maria Nuova (ASMN) - Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS), Reggio Emilia, Italy; University of Modena and Reggio Emilia, Italy.
Giovanni Battista
GB
La Sala
D000328:Adult; D015925:Cryopreservation / Q000379:methods*; D010064:Embryo Implantation / Q000502:physiology*; D004624:Embryo Transfer / Q000379:methods*; D005260:Female; D006801:Humans; D011247:Pregnancy; D018873:Pregnancy Rate; D027724:Reproductive Techniques, Assisted; D012189:Retrospective Studies
ART; Embryos; Freezing; Infertility; Outcome