Chinese scientists uncover why many IVF embryos stop developing
Chinese scientists have identified a key cause of early developmental failure in human embryos, a breakthrough that could help improve the success rates of in vitro fertilization (IVF), reports a Qazinform News Agency correspondent.
The findings, published in the journal Cell, come from a study led by researchers at Tsinghua University, who captured the first high-resolution images of human embryos during their first five days of development.
More than half of fertilized human eggs fail to reach the blastocyst stage, when embryos are ready for implantation in the uterus. To investigate why this occurs, researchers developed a dual-view light sheet microscope capable of recording living embryos over extended periods without causing damage.
The team analyzed more than 2,000 cell divisions in over 150 human and monkey embryos. They found that over 70% of embryos that stopped developing experienced abnormalities during their second cell division. In many cases, defects were linked to the spindle, a cellular structure responsible for distributing genetic material evenly between cells.
Researchers also identified abnormalities in centrosomes, cellular structures that help form the spindle. When centrosome numbers were incorrect, chromosome segregation errors occurred, often leading to developmental arrest.
Building on these findings, the scientists tested a low-dose drug designed to regulate centrosome replication during the second cell division. The proportion of embryos with normal centrosomes increased from 40% to 80%, while the treatment had no effect on embryos with already normal centrosomes.
“In the future, this discovery could be used to help prevent early embryo arrest in IVF clinics,” said Chun So, an assistant professor at Tsinghua University.
He added that the team will continue developing advanced imaging technologies to study human development after implantation, with the goal of creating new strategies to improve the chances of successful pregnancies.
Earlier, Qazinform News Agency reported that Turkish Health Minister Kemal Memişoğlu announced that surgeons at the Inonu University Liver Transplant Institute had successfully performed the world's first eight-way cross-liver transplant, marking a historic milestone in medical science.