Although it has been a topic of growing interest for a century, it is not clear how pre-eclampsia develops – until now.
Researchers believe they have now discovered the main cause of preeclampsia.
“We found a missing piece of the puzzle.” Researcher Gabriela Silva says, “Cholesterol crystals are the key and we are the first to unveil this.
Silva works at the Center for Molecular Inflammation Research (CEMIR) of the Norwegian University of Science and Technology (NTNU), a center of excellence, where she is part of a research group on infection during pregnancy led by Professor Anne Charlotte Everson.
The results are good news for nearly three percent of pregnant women in Norway with the disease. Preeclampsia is a major cause of illness and death in both the mother and the fetus worldwide.
In early pregnancy, the placenta does not develop properly, and the baby sometimes receives very little nutrition.
Often the symptoms of preeclampsia are mild, but in some cases the condition becomes so severe that the baby needs premature birth.
Preeclampsia does not go away until the baby is born. Since no one understands why this condition occurs, current treatment is to monitor and relieve symptoms.
Silva believes that future treatment will now be more effective.
“Pregnancy is actually a kind of natural inflammatory condition, and in preeclampsia, the inflammation becomes very strong and leads to disease,” Silva says.
Women with pre-eclampsia have an increased risk of developing cardiovascular disease later in life.
It was precisely this association that led researchers to choose to screen for cholesterol in pregnant women with preeclampsia. Cholesterol is a major cause of cardiovascular disease.
Cholesterol crystals are found in plaque that clogs blood vessels. Crystals form when bad cholesterol builds up in the walls of blood vessels. Studies have shown that cholesterol crystals are a strong initiator of inflammation in the body and can cause blood to clot.
Cholesterol crystals are identified as harmful substances in the body that need to be eliminated. But the defensive cells that come to do the task are unable to destroy it. They are calling for reinforcements, and more immune cells are coming in to no avail. The immune response increases, and the inflammatory process escalates.
Silva found that inflammation was highest in the region called the maternal-fetal interface, where the maternal cells come into direct contact with the fetal cells. This occurs in the placenta and the uterine wall.
“This direct contact means that inflammation directly affects the contact between mother and fetus and contributes to increasing inflammation in the mother,” Silva says.
Cholesterol levels are high in all pregnant women, because both the fetus and the placenta need cholesterol. But levels were higher in women with pre-eclampsia. They also have a lot of bad cholesterol, which is the type of cholesterol found in people at high risk of developing cardiovascular disease.
Silva did his best to solve the mystery. Tissue samples from a biobank established by the CEMIR research group were used, and included placental samples from 90 women with pre-eclampsia obtained immediately after birth. So the researchers obtained tissue samples from the uterine wall and the placenta. Samples were examined using sophisticated microscopes.
It took years of research to come to the conclusion.
Future treatment for preeclampsia might simply include statins, such as statins, but more research is needed to clarify their effects.
“Some women have an increased risk of preeclampsia from the start. They should be monitored with cholesterol checks. It is not done regularly today, but it has to be done regularly in the future. It is now not recommended that statins be used during pregnancy, but many clinical studies are looking closely at This shows that pravastatin, for example, can be safe to use during pregnancy, Silva says.