In-vitro fertilization (IVF) scientists have developed a new method to assess the quality of women's eggs and determine which are more likely to result in pregnancies.
Barry Behr, PhD. HCLD, associate professor of obstetrics and gynecology at the Stanford University School of Medicine and director of Stanford's IVF laboratory, described a way to "profile" the eggs to know their chances of success.
Metabolomic testing reveals trace molecules remaining after an array of cellular processes.
Previous studies have shown that metabolomic profiling can be used to identify unique biomarkers left behind by embryos in culture, which foretell the embryos with the highest reproductive potential in IVF.
"Think of it as a sort of smog test for the embryo. It tells you how clean the engine is burning, and whether there are any problems," said Behr.
For the study, the researchers, first extracted eggs from 43 women, then incubated them in culture for three hours and finally examined their metabolomic results before fertilization.
Then, the researchers documented what happened to each egg-whether it was fertilized, the quality of the resulting embryo on days three and five, and whether it led to a successful pregnancy.
The researchers established a correlation between the number of particular trace elements left behind by the eggs and both embryo viability and pregnancy rates.
"This shows we can predict embryo development and viability from the egg," said Behr.
Behr further said that the test could someday be used to predict the success of IVF and help determine which eggs should be selected for fertilization or to be frozen.
Using only the best-quality eggs would lead to the creation of fewer embryos and eliminate the need to keep large quantities of embryos in storage.
This could also help doctors avoid the practice of implanting numerous embryos into a woman, which sometimes leads to the birth of twins, triplets and higher-order multiples.
The study appeared in a recent issue of Reproductive Biomedicine Online.