Effect of Day 3 and Day 5/6 Embryo Quality on the Reproductive Outcomes in the Single Vitrified Embryo Transfer Cycles

Abstract

ObjectiveTo explore the live birth rate and neonatal outcome after single vitrified blastocyst transfer versus single vitrified cleavage-stage embryo transfer at different grades of embryo quality.MethodsA retrospective cohort study including 6077 single vitrified-thawed embryo transfer cycles was performed in the time-period from January 2013 to December 2018.ResultsAfter controlling for potential confounding variables, there are 161% increased odds of a live birth after transfer of single good quality embryo at day 5, 152% increased odds of a live birth after transfer of single poor quality embryo at day 5, 60% increased odds of a live birth after transfer of single good quality embryo at day 6 compared with transfer of single good quality embryo at day 3. Results from the generalized estimated equation regression showed significant relationship of unadjusted birth weight with development stage of embryo and embryo quality (good quality embryo on day 5 vs. Good quality embryo on day 3:β=108.55, SE=34.89, P=0.002; good quality embryo on day 6 vs. Good quality embryo on day 3:β=68.80, SE=33.75, P=0.041). However, no significant differences were seen in birth weight between transfer single poor quality embryo on day 5, 6 and transfer single good quality embryo on day 3.ConclusionA significant increase in live birth rate and birth weight after transfer of single good quality embryo on day 5 and day 6 compared with transfer of single good quality embryo on day 3 in the vitrified embryo transfer cycles.

Day-3 vs. Day-5 fresh embryo transfer

“…However, it has been shown that frozen embryo transfer on day five was associated with a lower birthweight compared to frozen embryo transfer on day three (De Vos et al, 2018). On the contrary, another study with large samples has shown that there was a significantly higher birth weight after good-quality blastocyst transfer on day five or day six compared to day-3 embryo transfers (Wang et al, 2021). Multiple births are the complication associated with multiple embryos transferred, associated with adverse health outcomes, including low birth weight.…”

Birthweight After Frozen Embryos Formed on the Fifth Day Versus the Sixth Day: A Retrospective Analysis Including 17,127 Singleton Newborns

“…Existing data on the effect of culture duration on neonatal birth weight are conflicting. Some studies have reported that compared with cleavage embryos, blastocyst transfer tends to have a higher mean birth weight and an increased proportion of LGA ( 9 , 10 , 28 ). An animal study has demonstrated that the effects of delayed blastulation and extended culture on blastocysts can be cumulative ( 26 ).…”

“…Previous findings have indicated that frozen embryo transfer (FET) is associated with a higher birthweight and an increased risk of delivering LGA babies as compared to fresh embryo transfer ( 7 , 8 ), implying that the process of cryopreservation can adversely affect the embryo quality and developmental potential. Moreover, FET at the blastocyst stage is associated with higher birthweight and an increased risk of LGA compared with the cleavage stage ( 9 , 10 ). However, limited studies have compared the perinatal outcomes after the transfer of frozen-thawed blastocysts formed on D5 and D6, and the results remain controversial ( 11 , 12 ).…”

The fatty acid composition in follicles is related to the developmental potential of oocytes up to the blastocyst stage: a single-centre cohort study

“…With regards to the ART outcome, several meta-analyses suggested a negative association between female obesity and live birth rates [ 5 – 7 ], while no adverse effects of obesity on pregnancy or live birth outcome have been reported in others [ 8 , 9 ]. Although embryo quality largely determines the success of implantation and live birth [ 10 ], Herbemont et al [ 11 ] indicated that poor or good embryo quality at days 2 and 3 were not predictive of the implantation of good-quality blastocysts. On the other hand, an increase in live birth rate was associated with blastocyst transfer on day 5 when compared with embryo transfer on day 3 [ 10 ].…”

“…Although embryo quality largely determines the success of implantation and live birth [ 10 ], Herbemont et al [ 11 ] indicated that poor or good embryo quality at days 2 and 3 were not predictive of the implantation of good-quality blastocysts. On the other hand, an increase in live birth rate was associated with blastocyst transfer on day 5 when compared with embryo transfer on day 3 [ 10 ]. Interestingly, the study by Blank et al [ 12 ] revealed that pregnancy outcome could be enhanced when transferring an embryo that has an improvement in quality between days 3 and 5 as opposed to one that has remained stable.…”