A new method for picking the 'right' egg in IVF

June 1, 2012 By Karen N. Peart, Yale University

(Medical Xpress) -- In a groundbreaking study, Yale School of Medicine researchers and colleagues at the University of Oxford have identified the chromosomal make-up of a human egg. This discovery may soon allow them to avoid using abnormal — or aneuploid — eggs during infertility treatments, and instead to pick eggs that are healthy enough for a successful in vitro fertilization (IVF) cycle.

The results are published in the May issue of the journal Human Reproduction.

Only a few oocytes () per IVF treatment cycle are able to produce a pregnancy because many eggs have the wrong number of chromosomes. If the egg is missing a chromosome or has an extra chromosome, this is referred to as aneuploidy. This problem increases as women age.

Oocytes are surrounded by cells, called cumulus cells, which regulate and assist the process of egg maturation. In this study, Yale Fertility Center director Dr. Pasquale Patrizio, and Dagan Wells of the University of Oxford studied genes expressed in the cumulus cells. They were able to identify a set of genes that are less active in cells that are associated with abnormal eggs.

They characterized two genes — SPSB2 and TP5313 — and found that the expression of these genes was consistently underrepresented in cumulus cells that surrounded abnormal eggs, while these same genes were normally expressed in eggs with the correct number of chromosomes.

“The identification of these in cumulus cells can serve as a novel, non-invasive marker to identify abnormal oocytes and thus ultimately improve success rates,” said Patrizio, professor in the Department of Obstetrics, Gynecology & Reproductive Sciences at Yale. “We can use surrounding the eggs to gain insight into the health of an egg. These cells are now able to inform us about the chromosomal makeup of an egg. This can help us know if it is the ‘right egg’ to be fertilized and produce a baby.”

“This finding opens up the possibility of a safe, effective, and inexpensive way of identifying healthy eggs, potentially lowering the risks of miscarriage and Down syndrome,” said Wells. “By conducting these tests before eggs are fertilized, ethical concerns about analysis of human embryos are avoided.”

Other authors on the study include Elpida Fragouli, Amy E. Lager, and Umit A. Kayisli.

Wells is supported by the National Institute for Health Research Biomedical Research Centre, Oxford; the work was also supported by a grant from Gema Diagnostics, Inc.

Explore further: Test for chromosome abnormalities sheds light on genetic origins of faulty eggs

More information: Human Reproduction, doi: 10.1093/humrep/des170

Related Stories

Test for chromosome abnormalities sheds light on genetic origins of faulty eggs

July 5, 2011
Researchers are developing a new way to test a woman's egg for chromosome abnormalities that avoids the need to manipulate and biopsy the egg itself. The research may also shed light on the crucial role played by certain ...

Discovery of a molecule that initiates maturation of mammalian eggs can lead to more IVF pregnancies

March 5, 2012
Women who have eggs that cannot mature will not become pregnant, and they cannot be helped by in vitro fertilization (IVF). Now researchers at the University of Gothenburg, Sweden, have identified a molecule called Cdk1 that ...

Researchers confirm key feature of age-related miscarriages and birth defects

April 14, 2011
Washington State University researchers have confirmed a critical step in cell division that results in age-related miscarriages and birth defects, including Down syndrome.

Recommended for you

Rise in preterm births linked to clinical intervention

January 18, 2018
Research at the University of Adelaide shows preterm births in South Australia have increased by 40 percent over 28 years and early intervention by medical professionals has resulted in the majority of the increase.

New report calls into question effectiveness of pregnancy anti-nausea drug

January 17, 2018
Previously unpublished information from the clinical trial that the U.S. Food and Drug Administration relied on to approve the most commonly prescribed medicine for nausea in pregnancy indicates the drug is not effective, ...

New study finds 'baby brain' is real, but the cause remains mysterious

January 15, 2018
So-called "baby brain" refers to increased forgetfulness, inattention, and mental "fogginess" reported by four out of five pregnant women. These changes in brain function during pregnancy have long been recognised in midwifery ...

Sleep quality improves with help of incontinence drug

January 12, 2018
A drug used to curtail episodes of urinary incontinence in women also improves quality of sleep, a researcher at the Stanford University School of Medicine reports.

Frozen embryos result in just as many live births in IVF

January 10, 2018
Freezing and subsequent transfer of embryos gives infertile couples just as much of a chance of having a child as using fresh embryos for in vitro fertilization (IVF), research from Ho Chi Minh City, Vietnam, and Adelaide, ...

Study suggests air pollution breathed in the months before and after conception increases chance of birth defects

January 8, 2018
A team of researchers with the University of Cincinnati and Cincinnati Children's Hospital has found evidence that indicates that pre-and post-pregnant women living in an area with air pollution are at an increased risk of ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.