Pathologists Say that Valuable Information is Being Lost by Discarding the Placenta After Birth

In an opinion article published in Cell Press’s journal “Trends in Molecular Medicine,” physicians and scientists argue that placental pathology is underutilized clinically because most placentas are discarded after birth. It should be a routine part of obstetric and neonatal care and also deserves more attention in research.

“Placentas should not be considered waste tissue,” says senior author Mana Parast, MD, PhD, a professor of pathology at the University of California San Diego School of Medicine. ”They can teach us a lot about what went wrong in a pregnancy, but also inform subsequent pregnancies for the health of the pregnant person and the baby.”

Why Placenta Research is So Important

The placenta is essential for the exchange of nutrients and waste products between the developing offspring and the pregnant person. When the placenta becomes diseased, it can affect both mother and child, both during pregnancy and later in life. In the worst case, a placental pathology can lead to stillbirth. This is the medical scenario in which placentas are most often clinically examined. However, various types of placental pathology are also associated with small fetal size and neurological problems in infants, as well as with high blood pressure (preeclampsia) and other cardiovascular problems in the mother.

Placental pathology may not only identify the cause of an adverse outcome in the baby, but also provide insight into why something happened to the mother and what that means for her future health. For example, researchers have found that a particular lesion in the placenta called decidual arteriopathy may be a marker for future cardiovascular disease in women, and other lesions can help predict whether preeclampsia or stillbirth will recur in subsequent pregnancies. Examination of the placenta of preterm infants can also be important for their immediate care, as it helps to detect fungal infections that would otherwise take days to identify.

Premature babies treated in the neonatal intensive care unit usually receive antibiotics to prevent bacterial infections that may have already taken hold, as premature babies do not have very good immune systems. However, they are not given antifungals,” says Parast. ”Culturing blood samples for fungal infection takes a few days, but if we quickly examine the placenta of preterm infants for signs of fungal infection, we can immediately notify the neonatal intensive care unit team to include an antifungal in the treatment.”

In the US, there are hospitals where all placentas are examined by pathologists, even in uncomplicated pregnancies, and sometimes this examination leads to further investigations, but this definitely requires many more resources. Although the effects of some patterns of placental pathology are known, others remain unclear, and very little is known about why these placental problems occur. For these reasons, the researchers say that placental research deserves more research funding and must be included in prospective clinical studies. Incorporating placental assessments into ongoing clinical studies will provide more information about how various placental lesions are related to the current and future health of patients and the pathophysiological causes underlying these lesions.