Preserved forearm endothelial responses with acute exposure to progesterone: A randomized cross-over trial of 17-beta estradiol, progesterone, and 17-beta estradiol with progesterone in healthy menopausal women.

Authors: Mather KJ, Norman EG, Prior JC, Elliott TG.

Publication Year: 2000

Citation: J Clin Endocrinol Metab 2000;85(12):4644-9.

Regularly menstruating women enjoy relative protection from cardiovascular disease. Until recently, this has been attributed to the function of estrogen, despite the fact that progesterone is also present. This study evaluated the differing acute effects of 17-beta estradiol with and without progesterone with progesterone alone on endothelial function in a randomized crossover trial.  Endothelial function was evaluated via endothelium dependent and independent forearm blood flow (FBF) using venous occlusion plethysmography. Flow responses were measured during brachial artery infusions achieving physiological levels of E2, E2 + P4, or P4 respectively along with either acetylcholine (an endothelium-dependent vasodilator), or sodium nitroprusside (an endothelium-independent vasodilator) in 27 healthy menopausal women with no cardiovascular disease risk factors. Small, statistically non-significant increases in endothelium-dependent flow responses were seen with all treatments. No impairment in response was seen with P4 alone or in combination with E2. The authors concluded that progesterone does not have detrimental vascular effects in humans.