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Updated: Aug 5, 2026
Semiconductor Sequencing for Preimplantation Genetic Testing for Aneuploidy
Published on: August 25, 2019
Maximizing pregnancy rates and limiting higher-order multiple conceptions by determining the optimal number of
Y Hu1, W S Maxson, D I Hoffman
1Northwest Center for Infertility and Reproductive Endocrinology, Margate, Florida 33063, USA.
Objective:
To define statistical thresholds for the number of embryos to be transferred to achieve an optimal pregnancy rate and keep higher-order multiple conceptions (pregnancy with more than two fetal sacs with cardiac activity) within an acceptable limit.
Design:
A retrospective review of patient records.
Setting:
Private practice assisted reproductive technology (ART) facility.
Patient(S):
Seven hundred fifty-four consecutive patients who underwent IVF-ET from 1994-1996.
Intervention(S):
Embryo grading and score system used on day 3 of embryo transfer.
Main Outcome Measure(S):
Implantation, pregnancy, and multiple conception rates.
Result(S):
For women < or =35 years old, transfer of up to four poor-quality, two fair-quality, or two good-quality embryos is optimal to eliminate any risk of higher-order multiple pregnancies. Transfer of four poor-quality, three fair-quality, or two good-quality embryos is recommended for women 36 to 39 years old. In women who are > or =40 years old, five embryos need to be transferred regardless of embryo quality.
Conclusion(S):
The mean cumulative embryo score can be used as a reference to determine an optimal number of embryos to transfer and to predict pregnancy outcome.
