Influence of different post-thaw culture time on the clinical outcomes of different quality embryos

Abstract

Background. In thawed embryo transfer cycles, the most common method is to transfer the embryos after 2 h of culture. Clinical outcomes of frozen-thawed cleavage embryo transfer cycles regarding the embryos status and the culture time of frozen-thawed cleavage embryos were limited and did not elucidate all unclear issues. Objectives. The objective of this study was to examine the clinical outcomes of frozen-thawed cleavage embryo transfer cycles according to the embryos status and the culture time (2 h or overnight). Material and methods. In this retrospective study (5-year period), 1,654 frozen-thawed embryos were analyzed. Firstly, frozen-thawed cleavage embryos were divided into 2 groups according to their status as follows: with at least 1 optimal embryo and without optimal embryos. Secondly, both of them were divided into 2 groups according to the culture time (2 h or overnight). Age of the female, infertility factors, clinical pregnancy, implantation rate, and live birth rate were compared. Results. There were no statistically significant differences in the pregnancy rate, the implantation rate, live birth rate, the miscarriage rate, and the ectopic pregnancy rate in each group. However, the implantation rate increased after 2 h of incubation (41. 1%) compared to overnight incubation (36.0%) in the group with at least 1 optimal day-3 embryo (p < 0.05). The cancellation rate in the suboptimal day-3 embryos group (9. 1%) was higher than in the group containing at least 1 optimal embryo (0.2%) for the long (overnight) culture (p < 0.05). Conclusions. The implantation rate can be improved in the optimal day-3 embryos transferred after 2 h of culture, but not for suboptimal day-3 embryos. Some unnecessary transfers can be avoided after overnight culture because of no further cleavage of the embryos.

The Effect of Post warming Culture Period Between Thawing and Transfer of Cryopreserved Embryos on Reproductive Outcomes After In Vitro Fertilization (IVF): A Systematic Review and Meta-analysis

“…Wang et al ( 6 ) retrospectively analyzed outcomes from 1654 frozen embryo transfers. Results, depending on whether a good quality embryo had been transferred or not, were included in their analysis.…”

“…Embryo quality has been related to reproductive results ( 6 ). The culture environment seems to play an important role in embryo survival and thus in its implantation capacity and reproduction.…”

Using affected embryos to establish linkage phase in preimplantation genetic testing for thalassemia

“…Hormone replacement therapy was used to prepare the uterine endometrium. A frozen non-pathogenic blastocyst with euploid karyotype was thawed and cultured for 2 hours before being transferred into the uterus as previously described [ 15 ]. Clinical pregnancies (CP) were defined after observation of a gestational sac with or without a fetal heartbeat on ultrasound evaluation 4 weeks after frozen embryo transfer (FET).…”

Pregnancy rates from transfer of embryos cryopreserved on day 5 versus day 3 with post-thaw culture

“…Regarding the post-thaw duration of the culture of cleavage stage embryos, Wang et al [8] demonstrated no benefit of an overnight culture of 'optimal' day 3 embryos (embryos with 7 to 8 equally sized mononucleated blastomeres and <10% fragmentation) compared to a 2-hour wait before transfer. However, cycles with an overnight culture of their 'suboptimal' embryos had a higher incidence of cancellation than those that had at least one 'optimal' embryo.…”