Researchers at the Cincinnati Children’s Hospital and the University of Cincinnati have discovered a link between the risk of placental accreta and a gene mutation, which can prevent the development of ‘natural killer’ cells, a type of white blood cell that can help the body fight against cancer tumors as viral infections. During normal childbirth, the placenta is delivered shortly after the delivery of the newborn, but in some cases, the placenta gets so deeply attached to the woman’s uterus that it cannot be extracted without the risk of massive blood loss, which can be fatal. In several instances, the emergency surgery performed to save the mother’s life can diminish her chances of bearing any more children.
Placental accreta is diagnosed in one out of every 272 births. The researchers have not only identified the connection but have also demonstrated in mice, a way that could prevent accreta from progressing. A co-author of the study, Helen Jones, Ph.D. and an expert in Placenta Research, Cincinnati Children’s, says that it is a massive concern related to maternal health. Currently, accreta can only be diagnosed by spotting it mid-pregnancy on ultrasound, typically after 18 to 20 weeks, and many women are unaware that they have it until the delivery, adds Jones. Jones mentions that if future studies confirm that women facing accreta also have the natural killer cells, it might be possible to limit the attachment and diminish the need for fertility-ending hysterectomies.
The collaborators discovered that the mice carried a mutation in the protein Gab3, which prevented the normal expansion of natural killer cells in the uterus. This obstructed the cell from stopping the process that enables the growing embryo to bind to tissues inside the uterus. This process, known as trophoblast invasion, typically goes on for about twenty weeks of pregnancy, but in women with accreta, the process can last even longer. The team’s findings have been published in the journal Science Immunology.