The placenta may be dismissed as “afterbirth,” deemed an afterthought in discussions about pregnancy and even relegated, literally, to the trash bin. But at long last it is beginning to get its due.

In the past three weeks, scientists have published three significant studies of this ephemeral organ. One gave a detailed analysis of all the genes expressed, or converted into functioning proteins, in the placenta; another experimented with a way to silence that expression when it causes trouble. In the third, researchers created mini-placentas, three-dimensional clusters of cells, or organoids, that mimic the real thing in the lab, and can be used as models for studying it.

In addition, at a recent meeting in Bethesda, Md., of the Human Placenta Project, several teams of researchers showed off sophisticated new techniques that enable the placenta to be studied in real time. That work could help doctors diagnose dangerous complications in pregnancy — including pre-eclampsia (a form of high blood pressure), preterm birth and fetal growth restriction — early enough to intervene. It might also help to reveal why boys are much more vulnerable than girls to disorders of brain development, including schizophrenia, A.D.H.D., autism, dyslexia and Tourette syndrome.

“The missing link between complications during pregnancy and development of the fetal brain has been hiding in plain sight for a long time,” said Dr. Daniel R. Weinberger, director of the Lieber Institute for Brain Development in Baltimore, Md. “It’s the placenta.”