KU Leuven: New human embryo research model opens doors to improved in vitro fertilization (IVF) and pregnancy prevention

A study by UZ Leuven last year showed that the chances of success of an IVF treatment are overestimated, which can cause great disappointment among intended parents. “The implantation of embryos in the uterus after implantation is very difficult to study for ethical reasons. Usually the right human cells can be called upon, but with embryos – even if they only consist of about 300 cells – this is of course much more difficult, especially if you want to bring them into contact with cells of the uterus so that they really can implant and develop”, says professor Hugo Vankelecom of the Department of Development and Regeneration of KU Leuven.

“Using stem cells, we have now succeeded in mimicking developing embryos at a very early stage, enabling us to bring them into contact with uterine cells in the lab to investigate which processes are important for proper implantation and further development.” Initial success has already been achieved through the characterization of lysophostatidic acid (LPA), a molecule that is already known for other processes but which the researchers have now discovered has a positive effect on the formation of these stem cell-derived embryos in the lab. “Naturally occurring molecules such as LPA could increase the success rates of IVF treatments, so that parents are less likely to be disappointed and have better control over their desire to have children,” says Dr Nicolas Rivron of the Biocenter in Vienna.


Preventing implantation

In addition to the search for molecules that improve the development and implantation of implanted embryos, molecules that prevent implantation are also being looked at. “This new cell model will give us more insight into the origin of pregnancy. We want to use this knowledge on the one hand to help prospective parents, but on the other it can also lead to new resources for people who do not (yet) want to have children,” explains Vankelecom. SC144, for example, is a molecule that ensures that simulated embryo cells no longer ‘stick’ properly when they are brought into contact with uterine cells, which hinders implantation. “The big advantage of this is that hormones do not have to be used, which is the case with most contraceptives.”