IVF Blood Clot Risk Eyed In New Study

New research on in-vitro fertilization (IVF) and blood clots resulting has come out of Sweden, and, while the danger is “slight,” the information could be useful to mothers at risk for the complication.

The IVF blood clot and pulmonary embolism risk was pinpointed in research out of the Karolinska Institute in Sweden where scientists looked at the increase in likelihood of such events in pregnancies assisted by IVF. The medical procedure, which is considered safe, is a treatment for infertility in which an egg is fertilized and implanted after fertilization for women with difficulty conceiving unassisted.

The IVF study discovered that the risk of blood clots and pulmonary embolism (in which an artery to the lung becomes blocked by a clot) is higher during the first trimester of pregnancy for women who used IVF versus those who conceived naturally.

New research from the found women who became pregnant through IVF are at increased risk for pulmonary embolisms – a blockage of a major artery in the lung – and venous thromboembolism (blood clots) during the first trimester of pregnancy.

Peter Henriksson is a professor and chief physician at the Karolinska Institute, and he explains that researchers set out to determine whether IVF posed a blood clot risk to mothers, due to heightened levels of estrogen needed for the procedure to work — a circumstance known to increase blood clot risk.

Henriksson explained to Fox:

“I didn’t believe that because when you do IVF procedure, you have to stimulate the follicles of the ovaries to get the eggs to harvest … The estrogen levels increase, and high estrogen levels are linked with increased propensity of blood to coagulate.”

stress and IVF

He adds:

“If a part of that blood clot breaks, circulation will carry that blood clot to the right side of the heart and further on to the pulmonary artery … And in the pulmonary artery, the blood clot could hinder circulation. If the clot is great or there are repeated emboli (blockage), then it could completely block circulation, and that is…potentially very dangerous.”

Lead study author Henriksson and his team looked at data from 23,498 women who had undergone IVF and 116,960 women conceived naturally, with an average age among both groups at 33. Fox explains:

“Through the use of public health records, the researchers determined how many of the women had been diagnosed with pulmonary embolism (PE) and venous thromboembolism (VTE) during their first trimester. Of the women who had done IVF, 4.2 out of 1,000 were diagnosed with VTE, compared to only 2.5 out of 1,000 those who had normal pregnancies.”

The IVF study centering on blood clots could be significant, as pulmonary embolism (a complication of blood clots) is currently the leading cause of maternal mortality.