Microscopy image of a PGA at day 8 showing the early tissues supporting the embryo, including the amniotic sac and the yolk sac-like structures, surrounded by (extra-embryonic) mesoderm tissue.

The yolk sac is the lone site of primitive hematopoiesis. However, the role of the yolk sac in generating definitive hematopoietic progenitors has remained controversial since the onset of circulation ...

The role of the human yolk sac in supporting early embryonic development and the first wave of the prenatal immune system has been mapped in a study published today (17 August) in Science. Researchers ...

A newly created cell model of the amniotic sac could reveal new insights into early pregnancy, as well as generate helpful products for medical use. When you purchase through links on our site, we may ...

Gastrulation, the process where an embryo reorganizes itself from a hollow sphere into a multilayered structure, is considered a 'black box' of human development. This is because human embryos are ...

During pregnancy, the amniotic sac quietly protects your baby every day. How does this thin, fluid-filled membrane stretch ...

A group of scientists has now demonstrated the presence of precursors of the placenta and the amniotic sac in synthetic embryos they created from mouse stem cells. In their effort to understand the ...

In a longitudinal study published in Scientific Reports, researchers investigate the effect of maternal physical activity on the size and growth of the yolk sac during early pregnancy. To this end, ...

The signals orchestrating the transformation of cells into the highly organized structures of embryos have remained hidden from observation inside the womb. Now, scientists have illuminated early ...