Heart health begins in the womb
Dr. Adrianne Watson - 27 January 2026
First Author Dr. Murilo Graton
Cardiovascular disease is the second leading cause of death for Canadians, accounting for almost 20% of all deaths in 2024. We are all familiar with how lifestyle or “environment” can impact our cardiovascular health. Exercising regularly, eating a balanced diet, and getting enough sleep may reduce risk of cardiovascular disease, whereas stress, smoking cigarettes, and high cholesterol increase risk. However, it is not just our adulthood habits that can change our risk for cardiovascular problems.
For some, the risk begins in the womb.
Pregnancies have complications that can be harmful or deadly to the mother or baby. We usually think about the effects of these complications in the short term such as gestational diabetes increasing risk of infantile jaundice, pre-term delivery leading to low birth weight, bleeding increasing risk of c-section. Luckily, the majority of infants born with these types of complications grow up to be healthy adults. However, some pregnancy complications can have lifelong implications.
One such complication is preeclampsia. Preeclampsia is a highly dangerous complication arising in mid-late pregnancy. Approximately 5-8% of mothers are affected, and it is a leading cause of maternal and fetal morbidity and mortality. Preeclampsia reduces the nutrients and oxygen delivered to the baby, which can reduce fetal size and result in preterm or still births. The exact cause of the disorder is unidentified, and yet in Canada, rates are on the rise.
In addition to the acute risks of preeclampsia to the fetus during pregnancy, offspring of preeclamptic pregnancies have an increased risk of developing cardiovascular disease later in life. The exact mechanism is still not understood but a recent study from Dr. Sandra Davidge’s group in the journal, Bioscience Reports brings us one step closer to understanding why.
In pregnancy, temporarily high cholesterol (hypercholesterolemia) is normal, and required to help the fetus grow and thrive. However, exceedingly high cholesterol can increase the chance of developing preeclampsia. In previous studies with rats, high cholesterol pregnancies lead to similar outcomes seen in preeclampsia pregnancies, and is used to model this risky complication.
Using this model, Dr. Murilo Graton, a postdoctoral researcher in the Davidge lab, asked how excessive hypercholesterolemia in pregnancy could lead to long term cardiovascular consequences in offspring.
Pregnant rats were fed a high-cholesterol diet to induce excessive hypercholesterolemia. At 4 months (roughly equivalent to a young adult human), the cardiovascular health in the offspring was assessed.
Not surprisingly, the initial cardiac tests came back normal, such as blood pressure and heart function. But when they looked at the larger cardiovascular system, particularly how the blood vessels act, they found some concerning problems.
We all know that blood vessels can widen and narrow - if you’ve ever jumped in a cold pool after the hot tub or sauna, you’ve seen it in action on your hands. When the artery narrows, it’s called vasoconstriction. When it widens, it’s known as vasodilation. This process happens throughout the body and is controlled by our body’s nervous system or by medications. In this study, when the vessels of these 4 month old rats were prompted to narrow or constrict, something very strange happened.
In female offspring, the aorta was not narrowing properly. While this may not cause acute problems, deficits in the thoracic aorta are linked to the development of atherosclerotic plaques or “blockages” in the heart. In male offspring, however, it was the coronary arteries (provides blood supply to the heart) that showed impaired vasodilation.They also had an increase in reactive oxygen species, which are by-products of cellular dysfunction and can cause tissue damage - which could assist in the development of a heart attack. Should a heart attack happen, the team revealed heart function would also be lessened.
As with any disease with a high level of environmental risk factors, it is easy to assume this is an individual problem due to lifestyle choices. However, this study is an important reminder our health can be influenced by factors outside of anyone’s control. This is why understanding conditions like preeclampsia are so important, both to help manage the long-term consequences that may be different for males versus females, and learn how to prevent it altogether.
This research was funded by the Canadian Institutes of Health Research (CIHR) and by the Stollery Children’s Hospital Foundation (SCHF) and the Alberta Women’s Health Foundation (AWHF) through the Women and Children’s Health Research Institute (WCHRI). Individual funding for the authors was provided by the SCHF and AWHF through WCHRI, Banting Postdoctoral Fellowship (CIHR), and Motyl Endowment Cardiac Sciences Summer Student Award.