The impact of culturing thawed split embryos to blastocyst stage on pregnancy outcome in patients with recurrent implantation failure
Objective:To investigate whether continuing the culture of thawed split embryos to the blastocyst stage can improve the pregnancy outcome in patients with recurrent implantation failure(RIF).Methods:A retrospective analysis was conducted on the clinical data of 587 patients with RIF who underwent frozen-thawed embryo transfer treatment in the Reproductive Medicine Department of Nanjing Drum Tower Hospital,Affiliated Hospital of Medical School,Nanjing University from January 2015 to December 2022.Among them,there were 45 patients who underwent continued blastocyst culture after thawing and cleavage embryo division(group A),299 who underwent thawed cleavage embryo transfer(group B),and 243 who underwent thawed blastocyst transfer(group C).Patients in group C were further divided into two subgroups based on the day of blastocyst formation as the Day 5 blastocyst transfer group(group C-D5,n=183)and the Day 6 blastocyst transfer group(group C-D6,n=60).The clinical outcomes including HCG positive rate,the implantation rate,clinical pregnancy rate,the miscarriage rate,live birth rate and so on,and average gestational age as well as birth weight of newborns were compared and analyzed among the groups.Results:Among the 56 patients who chose to continue culturing thawed blastocysts for embryo transfer,11 patients(19.64％)had their cycles canceled due to failed blastocyst culture.In terms of pregnancy outcomes,HCG positive rate(62.22％vs.45.15％,57.61％vs.45.15％),the implantation rate(49.12％vs.33.07％,44.48％vs.33.07％)and live birth rate(48.89％vs.33.78％,44.03％vs.33.78％)in group A and group C were significantly higher than those in Group B(P＜0.05).There was no significant difference in the miscarriage rate among the three groups(P＞0.05).The birth weight of newborns in group A was significantly higher than in group B and group C(P＜0.05).The implantation rate(49.12％vs.29.33％,48.70％vs.29.33％),clinical pregnancy rate(57.78％vs.38.33％,56.28％vs.38.33％),and live birth rate(48.89％vs.28.33％,49.18％vs.28.33％)in group A and group C-D5 were significantly higher than those in group C-D6(P＜0.05).In terms of the newborns,the birth weight of newborns in group A was significantly higher than those in group B and C(P＜0.05),there was no significant difference in the miscarriage rate among the three groups(P＞0.05),and the birth weight of newborns in group A and group C-D6 was significantly higher than that of group C-D5(P＜0.05).Conclusions:Thawing and culturing fragmented embryos to the blastocyst stage for transfer may potentially improve pregnancy outcomes in patients with RIF.In a frozen embryo transfer cycle,if the patient has D5 blastocysts cryopreserved,it is recommended to prioritize thawing and transfer them.If there are no cryopreserved D5 blastocysts,it is possible to consider thawing and culturing fragmented embryos to the blastocyst stage for transfer in order to achieve better clinical outcomes.
万方数据
维普
