Helping Protect the Placenta During Pregnancy
Dr. Nayiar Shahid - 10 August 2026
Dr. Amanda de Oliviera
Pregnancy depends on the remarkable organ known as the placenta. It acts as a baby’s life supply, delivering essential oxygen and nutrients while clearing waste. Normally, a placenta functions quite well without intervention but when underlying conditions are present, it might need some help to function properly.
One such example occurs in women with very high cholesterol levels. This condition, called excessive hypercholesterolemia, has been linked to an increased risk of preeclampsia, a dangerous pregnancy complication marked by high blood pressure and damage to organs, such as the kidneys and liver. Scientists believe that inflammation inside the placenta plays an important role in this process. The placenta fails to develop normally and this leads to a body-wide response that, if untreated, could be fatal for the mother.
Now, a recent study from Dr. Amanda de Oliveira, a postdoctoral fellow in Dr. Sandra Davidge’s research group, published in the American Journal of Physiology, reveals how low-dose aspirin may help protect the placenta during pregnancies complicated by very high cholesterol levels. Beyond its well-known role in thinning the blood, aspirin appears to quiet inflammation and help restore the placenta’s ability to support a healthy pregnancy.
The researchers studied normal pregnant rats as well as those with excessively high cholesterol levels designed to mimic inflammation. Some received low-dose aspirin throughout pregnancy, while others did not. The team then examined the placenta, and measured inflammatory signals, and analyzed an important balance between two proteins known as placental growth factor (PIGF) and soluble fms-like tyrosine kinase-1 (sFlt-1). During inflammation, the levels of PlGF drop and sFlt-1 rise. The hope was to regain that balance with the help of aspirin.
First came the expected results. Pregnancies with very high cholesterol levels showed greater inflammation in the placenta, especially in placentas with a male fetus. Also, as expected, the balance of the two proteins was disrupted with too much sFlt1 and not enough PlGF. As one might expect, this led to malformation of the placenta and the right conditions for preeclampsia.
Then came the results - after a daily provision of about 100mg of aspirin, just a little more than a low dose aspirin pill you might find in a store, the balance between SFlt-1 and PlGF was restored. The medication also altered the levels of immune factors in the placenta for the better.
However, there was a catch. The immune results were not universal. Changes differed depending on the sex of the offspring. As to the nature of the differences, they tended to occur with immune molecules known to be involved in consequences in other areas of the body, like the lung, the heart, and the urinary tract. How these changes will affect placental development and the risk for preeclampsia depending on sex will need to be further studied.
There appears to be little doubt that aspirin has potential to help those with very high cholesterol during pregnancy. However, these experiments were performed in rats, and more research is needed to know whether the same changes happen in humans. Low-dose aspirin is already recommended for some people at high risk of developing preeclampsia, but not necessarily in pregnancies with excessive hypercholesterolemia. These findings demonstrate how aspirin can also improve pregnancy outcomes in this pregnancy complication and supports the need to have cholesterol levels measured during the reproductive years. .