News | Genetic Testing Identifies Why IVF Embryos Stop Developing and May Help Improve Success Rates
By genetically testing nearly 1,000 embryos, scientists have produced the most detailed analysis to date of what happens to human embryos after in vitro fertilization (IVF). Nearly half stopped developing early because of genetic abnormalities, suggesting that changes to fertility treatment processes could help more IVF pregnancies succeed. The study provides new insight into embryo development during IVF and the earliest stages of natural pregnancy.
Dr. Rajiv McCoy, assistant professor of biology at Johns Hopkins University, said most of these genetic errors did not arise when the egg formed but during cell division after fertilization. The finding suggests that modifying IVF procedures might reduce these errors and improve success rates. The results were published in Genome Medicine.
The team compared IVF embryos that stopped developing within days of fertilization with embryos that developed successfully, looking for genetic differences. Usually, only surviving embryos are genetically tested to determine which are suitable for transfer to the uterus. Dr. McCoy noted that understanding why embryos survive requires testing all embryos.
Some embryos initially developed normally because maternal genetic material controlled cell division. Problems emerged when the embryo's own genes took over. Although the embryonic cells initially received the correct 46 chromosomes, errors in chromosome number appeared during later cell divisions.
Chromosomal Abnormalities and IVF
Gains or losses of chromosomes, known as aneuploidy, are common in human embryo development. Although rare in other species, they occur frequently in human embryos. Scientists have long studied aneuploidy by screening IVF embryos and consider it a leading cause of pregnancy loss. Dr. McCoy said it may be an inherent feature of human reproduction and development, with important implications for IVF. Improved genetic testing may help increase IVF success rates.
The team plans to identify the parental origin of chromosomes in abnormal embryonic cells and investigate whether these errors relate to genes from either parent. It also hopes to improve embryo survival by adjusting the chemical composition of culture media.
Co-author Dr. Michael Summers of the London Women's Clinic said culture medium composition may contribute to abnormal cell division and that understanding these mechanisms could help prevent developmental arrest.
News | Genetic Testing Identifies Why IVF Embryos Stop Developing and May Help Improve Success Rates
News | Genetic Testing Identifies Why IVF Embryos Stop Developing and May Help Improve Success Rates
By genetically testing nearly 1,000 embryos, scientists have produced the most detailed analysis to date of what happens to human embryos after in vitro fertilization (IVF). Nearly half stopped developing early because of genetic abnormalities, suggesting that changes to fertility treatment processes could help more IVF pregnancies succeed. The study provides new insight into embryo development during IVF and the earliest stages of natural pregnancy.
Dr. Rajiv McCoy, assistant professor of biology at Johns Hopkins University, said most of these genetic errors did not arise when the egg formed but during cell division after fertilization. The finding suggests that modifying IVF procedures might reduce these errors and improve success rates. The results were published in Genome Medicine.
Genetic Testing Reveals Why Embryos Stop Developing
The team compared IVF embryos that stopped developing within days of fertilization with embryos that developed successfully, looking for genetic differences. Usually, only surviving embryos are genetically tested to determine which are suitable for transfer to the uterus. Dr. McCoy noted that understanding why embryos survive requires testing all embryos.
Some embryos initially developed normally because maternal genetic material controlled cell division. Problems emerged when the embryo's own genes took over. Although the embryonic cells initially received the correct 46 chromosomes, errors in chromosome number appeared during later cell divisions.
Chromosomal Abnormalities and IVF
Gains or losses of chromosomes, known as aneuploidy, are common in human embryo development. Although rare in other species, they occur frequently in human embryos. Scientists have long studied aneuploidy by screening IVF embryos and consider it a leading cause of pregnancy loss. Dr. McCoy said it may be an inherent feature of human reproduction and development, with important implications for IVF. Improved genetic testing may help increase IVF success rates.
The team plans to identify the parental origin of chromosomes in abnormal embryonic cells and investigate whether these errors relate to genes from either parent. It also hopes to improve embryo survival by adjusting the chemical composition of culture media.
Co-author Dr. Michael Summers of the London Women's Clinic said culture medium composition may contribute to abnormal cell division and that understanding these mechanisms could help prevent developmental arrest.
Source:
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