Chromosomal abnormalities in embryos from couples with a previous aneuploid miscarriage

Area of Science:

• Reproductive Medicine
• Genetics
• Embryology

Background:

• Aneuploid miscarriage, resulting from abnormal chromosome numbers, can occur after natural conception (NC) or assisted reproductive technology (ART).
• Preimplantation genetic screening (PGS) analyzes embryo chromosomes before implantation to detect abnormalities.

Purpose of the Study:

• To compare chromosomal abnormality rates in preimplantation embryos from couples with a history of aneuploid miscarriage (from NC or ART) versus a control group.
• To evaluate the impact of previous aneuploidy type (autosomal vs. sex chromosome) on embryo chromosomal status.

Main Methods:

• Retrospective study conducted at an IVF clinic.
• Involved embryo biopsy and fluorescence in situ hybridization (FISH) for chromosomal analysis.
• Compared aneuploidy rates, pregnancy, and implantation rates in patient groups.

Main Results:

• Significantly higher rates of chromosomal abnormalities were found in embryos from couples with previous autosomal aneuploidy (67.8% NC, 65.8% ART) compared to controls (34.0%).
• No significant difference in chromosomal abnormalities was observed for previous sex chromosome abnormalities compared to controls.
• Clinical outcomes showed a positive trend in patients with previous autosomal aneuploidy after NC.

Conclusions:

• Couples with a history of aneuploid miscarriage, particularly autosomal aneuploidy, exhibit a higher incidence of chromosomal abnormalities in their preimplantation embryos.
• Preimplantation genetic screening (PGS) is recommended for these couples to identify and potentially avoid aneuploid embryos.
• The study highlights the importance of considering a patient's history of aneuploidy when offering genetic screening services.