(USA)

Scientists have developed a structure using human stem cells that could hold the key to discovering why so many pregnancies falter in the early stages.

The team from the University of Michigan (UM) has managed to produce something similar to the amniotic sac, a key component in human development. Understanding why problems arise not long after the sperm meets the egg is vital to advancing research in this area.

“As many as half of all pregnancies end in the first two weeks after fertilization, often before the woman is even aware she is pregnant. For some couples, there is a chronic inability to get past these critical early developmental steps, but we have not previously had a model that would allow us to explore the reasons why,” explained UM Professor Deborah Gumucio. “We hope this work will make it possible for many scientists to dig deeper into the pathways involved in normal and abnormal development, so we can understand some of the most fascinating biology on earth.”

And because the new lab-grown structure – labelled a post-implantation amniotic sac embryoid, or PASE –  is made using stem cells, rather than with a donated embryo, the research avoids the ethical issues sometimes related to infertility research.