Related Experiment Video
Updated: Feb 8, 2026

Human Blastocyst Biopsy and Vitrification
Published on: July 26, 2019
Day 6 blastocyst is associated with increased birth weight in full-term singleton newborns after frozen-thawed
Jiali Cai1,2, Lanlan Liu1,2, Yingpei Xu1
1The Affiliated Chenggong Hospital, Xiamen University, Xiamen, 361002, Fujian, China.
Purpose:
The purpose of the study is to compare the newborns weight in singleton term birth following transfer of thawed blastocysts-frozen on either day 5 or day 6 after in vitro fertilization.
Method:
The retrospective study included 1444 frozen-thawed blastocyst transfer (FBT) cycles resulting in live singleton births between Jan 2013 and Dec 2016. The main outcomes measured were absolute birth weight, z-score adjusted for gestational age and gender, and incidence of large-for-gestational-age (LGA) newborns. Generalized linear model (GLM) and logistic regression were used in multivariate analyses.
Result(S):
Both the absolute birth weight (3416.49 ± 404.74 vs 3349.22 ± 416.17) and the z-score (0.6 ± 0.93 vs 0.41 ± 0.93) were significantly higher on day 6 FBT in comparison with day 5 FBT. The incidence of LGA newborns was also increased on day 6 FBT (22.8 vs 14.7%, P = 0.006). Adjusted for maternal age, BMI, PCOS diagnosis, present of vanishing twin, and embryo quality, the odds ratio (95% confidence interval) for LGA on day 6 FBT comparing with day 5 FBT was 1.76 (1.18-2.64).
Conclusion(S):
Day 6 FBT is associated with increased birth weight and contributes to the incidence of LGA newborns in FBT.
More Related Videos
15:00Daily Transfers, Archiving Populations, and Measuring Fitness in the Long-Term Evolution Experiment with Escherichia coli
Published on: August 18, 2023
09:35Modified MicroSecure Vitrification: A Safe, Simple and Highly Effective Cryopreservation Procedure for Human Blastocysts
Published on: March 2, 2017
Related Concept Videos
Birth Control Methods
Weighted Mean
For example, consider the number of goals scored in the matches of a tournament. While computing the average number of goals scored in the tournament, it may be more important to...
Increasing Function
Long-term Depression
Atomic Weight
Mass and Weight