Effects of elective double embryo transfer on pregnancy outcome in IVF-ET

Objective:To investigate the effect of elective double embryo transfer on pregnancy outcome in IVF-ET.Methods:The data of double embryos transfer of day 3from June 2012 to May 2014 in Reproductive Medicine Center of Tongji Hospital were retrospectively analyzed.A total of 517 cycles were divided into three groups according to the morphological scores of transferred embryos.Group A had two top quality embryos for transfer(304cycles),group B only one top quality embryo(128cycles)and group C two nontop quality embryos(85 cycles).The patients' age,duration of infertility,infertile causes,clinical pregnancy rate,take-home baby rate,live birth rate and other clinical outcome were compared among the three groups.Results:The clinical pregnancy rate per transfer cycle was 73.7%,62.5% and 43.5%,and the corresponding take-home baby rates per transfer cycle were 62.1%,51.6%and 36.5%in group A,B and C respectively,which significantly reduced along with the decrease of embryo morphological grade(P 0.05).However,there were no significant differences in ectopic pregnancy rate,early abortion rate,late abortion rate and live birth rate among the three groups(P0.05).The biochemical pregnancy rate ingroup C was significantly higher than that in group A and B(P0.05),but there was no significant difference between group A and group B(P 0.05).The live birth rate per transfer embryo was significantly higher in group A than that in group B and C(P0.05),but no significant difference was found between group B and C(P0.05).Conclusions:Embryo morphological grade could be used as a parameter to evaluate the potential of embryo development.The optimum clinical pregnancy rate and live birth rate per embryo could be achieved by transferring grade I embryos.Once the clinical implantation is established,the morphological grade of embryo would not influence pregnancy outcome.