Jl. English et al., EFFECT OF THE MENSTRUAL-CYCLE ON ENDOTHELIUM-DEPENDENT VASODILATION OF THE BRACHIAL-ARTERY IN NORMAL YOUNG-WOMEN, The American journal of cardiology, 82(2), 1998, pp. 256
In normal young women, endothelium-dependent, flow-mediated vasodilati
on is enhanced when serum estradiol levels are elevated and unopposed
by elevated levels of progesterone.