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Updated: May 7, 2026

Chromosome Screening of Human Preimplantation Embryos by Using Spent Culture Medium: Sample Collection and Chromosomal Ploidy Analysis
Published on: September 7, 2021
Diminished effect of maternal age on implantation after preimplantation genetic diagnosis with array comparative
Gary L Harton1, Santiago Munné, Mark Surrey
1Bluegnome, La Jolla, California.
Objective:
To assess the relationship between maternal age, chromosome abnormality, implantation, and pregnancy loss.
Design:
Multicenter retrospective study.
Setting:
IVF centers in the United States.
Patient(S):
IVF patients undergoing chromosome screening.
Intervention(S):
Embryo biopsy on day 3 or day 5/6 with preimplantation genetic diagnosis (PGD) by array comparative genomic hybridization.
Main Outcome Measure(S):
Aneuploidy, implantation, pregnancy, and loss rates.
Result(S):
Aneuploidy rates increased with maternal age from 53% to 93% for day 3 biopsies and from 32% to 85% for blastocyst biopsies. Implantation rates for euploid embryos for ages <35-42 years did not decrease after PGD: ranges 44%-32% for day 3 and 51%-40% for blastocyst. Ongoing pregnancy rates per transfer did not decrease for maternal ages <42 years after PGD with day 3 biopsy (48.5%-38.1%) or blastocyst biopsy (64.4%-54.5%). Patients >42 years old had implantation rates of 23.3% (day 3), 27.7% (day 5/6), and the pregnancy rate with day 3 biopsy was 9.3% and with day 5 biopsy 10.3%.
Conclusion(S):
Selective transfer of euploid embryos showed that implantation and pregnancy rates were not significantly different between reproductively younger and older patients up to age 42 years. Some patients who start an IVF cycle planning to have chromosome screening do not have euploid embryos available for transfer, a situation that increases with advancing maternal age. Mounting data suggests that the dramatic decline in IVF treatment success rates with female age is primarily caused by aneuploidy.
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