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Updated: Jul 2, 2026
Ultrasound Assessment of Endothelial-Dependent Flow-Mediated Vasodilation of the Brachial Artery in Clinical Research
Published on: October 22, 2014
Endothelial function, endothelin-1, and fibrinogen in young women using the vaginal contraceptive ring
Britta N Torgrimson1, Jessica R Meendering, Nicole P Miller
1Department of Human Physiology, University of Oregon, Eugene, Oregon 97403, USA.
Objective:
To assess the effects of the vaginal contraceptive ring cycle on indices of cardiovascular health and risk by studying healthy women during the active hormone phase compared with the ring-free phase of a standard 21/7-day cycle.
Design:
Observational prospective cohort; 4 weeks' duration.
Setting:
Department of Human Physiology, University of Oregon.
Patient(S):
Twenty healthy women.
Intervention(S):
Endothelial function testing using standard flow-mediated vasodilation of the brachial artery and sublingual nitroglycerin administration. All participants underwent venous blood collection.
Main Outcome Measure(S):
Endothelium-dependent and endothelium-independent vasodilation of the brachial artery using Doppler ultrasound imaging. Baseline levels of high-density lipoprotein, low-density lipoprotein, triglycerides, total cholesterol, endothelin-1, and fibrinogen.
Result(S):
The active hormone phase of the vaginal ring cycle showed significantly higher vasodilation compared with the ring-free phase. The active hormone phase also showed increased fibrinogen levels compared with the ring-free phase. Low-density lipoprotein lipid levels also fluctuated and were significantly higher during the ring-free phase.
Conclusion(S):
Preliminary study observations of improved endothelial function and lowered low-density lipoprotein levels during the active hormone phase versus the ring-free phase suggest that the vaginal contraceptive ring has beneficial effects on vascular health in women.
