Semaglutide Reduces Fetal Oxygen In Pregnancy Study
A new animal study found semaglutide, the active ingredient in Ozempic and Wegovy, significantly reduced maternal heart output and fetal oxygen levels in pregnant sheep within two hours, raising safety concerns for its use during pregnancy.
A University of Adelaide study has found semaglutide significantly reduced maternal heart output and fetal oxygen levels within two hours of administration in pregnant sheep. The research, published as a conference abstract in Heart, Lung and Circulation on November 10, 2026, used advanced magnetic resonance imaging to measure blood flow and collected fetal blood samples.
Within two hours of giving the drug, maternal heart output dropped. This reduction in cardiac output led to decreased blood flow to the uterus and, consequently, lower fetal oxygen levels. Dr. Mitchell Lock, a researcher on the study, explained that oxygen is essential for healthy fetal growth and development. Fetal blood pressure and heart rate were also monitored throughout.
Clinical Context And Medication Use
With hundreds of thousands of Australians and millions globally using GLP-1 medications for diabetes or weight loss, the study's immediate effects highlight urgent safety considerations. Semaglutide is the active ingredient in weight-loss medications such as Ozempic and Wegovy.
Approximately half a million people in Australia use GLP-1 medications for diabetes. About 12% of adults in the United States use these medications for weight loss.
Medical Guidance And Patient Concerns
Health authorities explicitly warn against semaglutide use during pregnancy, and women planning to conceive are advised to discontinue treatment beforehand. Despite this clear guidance, patients face practical challenges.
Many women are reluctant to stop medication to avoid regaining lost weight. Some women using the drug for diabetes have concerns about changing their established treatment regimen.
Expert Perspective On Knowledge Gaps
Researchers stress the need for further investigation into prolonged exposure effects, as current evidence remains limited to animal models. Professor Janna Morrison emphasized the need for further investigation into prolonged exposure to semaglutide during pregnancy.
Dr. Mitchell Lock said, "While weight-loss medications have become incredibly popular, there's still a lot we don't know about how they might affect a developing baby." The study focused on immediate effects and did not establish long-term impacts on fetal growth. It is unknown what happens with longer-term semaglutide use or whether similar effects occur in human pregnancies. The findings are preliminary and have not been demonstrated in humans.
Continued research into prolonged semaglutide exposure during pregnancy is now a priority for the scientific team.
