Correlation between embryological factors and pregnancy rate: development of an embryo score in a cryopreservation programme.
OBJECTIVE
To establish which embryo parameters, in frozen thawed embryo transfers, have the highest prognosis value in the establishment of pregnancy. The relative importance of different embryo parameters is used to develop an embryo score.


METHODS
Retrospective analysis of the implantation rate in 356 frozen/thawed single embryo transfers. A logistic regression model is used to establish an embryo score.


RESULTS
A direct correlation is established between the implantation rate and fresh embryo development (number of blastomeres and their symmetry), survival rate after thawing and mitosis resumption after overnight culture.


CONCLUSIONS
An embryo score is developed to determine the implantation potential of frozen/thawed embryos.
Servei de Medicina de la Reproducció, Departament d'Obstetrícia, Ginecologia i Reproducció, Institut Universitari Dexeus, Sabino de Arana, 5-19, 08028, Barcelona, Spain. miqsol@dexeus.com
Miquel
M
Solé
Josep
J
Santaló
Ignacio
I
Rodríguez
Montse
M
Boada
Buenaventura
B
Coroleu
Pere N
PN
Barri
Anna
A
Veiga
D001757:Blastomeres / Q000166:cytology / Q000502:physiology; D015925:Cryopreservation / Q000379:methods*; D010064:Embryo Implantation / Q000502:physiology*; D004622:Embryo, Mammalian / Q000502:physiology*; D005260:Female; D005307:Fertilization in Vitro / Q000379:methods; D006801:Humans; D008938:Mitosis; D011247:Pregnancy; D018873:Pregnancy Rate; D056826:Single Embryo Transfer