EmbryoIn vitro fertilization (IVF) is a scientific process which provides childbearing options to people whose natural options might not be so forgiving. For this process, though, scientists have to choose the right embryo to fertilize if they want to expect the successful gestation of a healthy baby.

A new study suggests that choosing the right egg might be as simple as finding the one with the right texture. Bioengineers at Stanford University say that they can measure the rigidity of an hour-old fertilized egg to effectively determine its viability.

Scientists say that this technique has the potential to improve the success rate for single-egg IVF, which could, of course, improve the overall prognosis for both the mother and the baby.

Presently, an IVF procedure involves embryo screening which involves the fertilization of an egg with a follow up examination five or six days later when the zygote reaches the 60-100-cell blastocyst stage. Scientists extract cells from the egg to evaluate its morphology, as well as the cell division rate. A scientists will then choose the “best-looking” embryo for transfer to the uterus.

But, while plucking just a few cells from the newly-formed blastocyst will increase the odds for successful embryo selection, it is an invasive process which can, unfortunately, put undue stress on the embryo. This often results in a 70 percent failure rate, which means the engineer needs to implant multiple embryos into the womb, hoping that just one will take hold; of course, this can also lead to other complications.

Lead study author Livia Yanez, of Stanford University, advises, “A lot of twins are born because we don’t know which embryos are viable or not, so we transfer several at one time. This can increase the risk of neonatal mortality and cause complications for babies and the mothers.”

And so, she goes on to say, “We wanted to develop a mechanical test that could ascertain embryo viability well enough that doctors could implant just one embryo and have a very good feeling that it would be viable.”


Stanford IVF Laboratory director, Barry Behr, however, suggested that some of the fertilized eggs were “squishier” than others; and this lead researchers to investigate if this had anything to do with a particular eggs overall quality of development.


“It is still surprising to think that simply squeezing an embryo the day it was fertilized can tell you if it will survive and ultimately become a baby,” insists David Camarillo, who is an assistant professor of bioengineering at Stanford University.

But sure, enough, they found this particular texture appeared to be associated with a higher success rate.

The results of this study have been published in the journal Nature Communications.