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Updated: Feb 16, 2026

Chromosome Screening of Human Preimplantation Embryos by Using Spent Culture Medium: Sample Collection and Chromosomal Ploidy Analysis
Published on: September 7, 2021
Cell-free DNA screening and sex chromosome aneuploidies
Michael T Mennuti1, Suchitra Chandrasekaran2, Nahla Khalek3
1Department of OB/GYN, Divisions of Maternal-Fetal Medicine and Reproductive Genetics, University of Pennsylvania, Philadelphia, PA, USA.
Abstract:
Cell-free DNA (cfDNA) testing is increasingly being used to screen pregnant women for fetal aneuploidies. This technology may also identify fetal sex and can be used to screen for sex chromosome aneuploidies (SCAs). Physicians offering this screening will need to be prepared to offer comprehensive prenatal counseling about these disorders to an increasing number of patients. The purpose of this article is to consider the source of information to use for counseling, factors in parental decision-making, and the performance characteristics of cfDNA testing in screening for SCAs. Discordance between ultrasound examination and cfDNA results regarding fetal sex is also discussed.
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