Placenta is initiated first, as cells of a fertilized egg divide and specialize

The first stages of placental development take place days before the embryo starts to form in human pregnancies. The finding highlights the importance of healthy placental development in pregnancy, and could lead to future improvements in fertility treatments such as IVF, and a better understanding of placental-related diseases in pregnancy.

Evaluating and Deploying Covid-19 Vaccines — The Importance of Transparency, Scientific Integrity, and Public Trust

An unprecedented effort is under way to rapidly develop Covid-19 vaccines, with pharmaceutical companies, academic researchers, and government agencies aiming to compress into several months a process that typically requires at least several years. This work is supported by extraordinary public and…