Research from Weill Medical College of Cornell University and other institutions provides new evidence that the sex steroid hormone progesterone is also a vasoactive hormone that directly affects blood vessels. This finding sheds light on both the drop in blood pressure that usually accompanies pregnancy (when progesterone levels are high) and the rise in blood pressure that often occurs in women after menopause (when the production of progesterone falls off). It may also focus and sharpen the debate on the value of female hormones in long-term cardiovascular protection. Weill Cornell Researcher Shows How Progesterone Is Not Just Sex Hormone but Blood Pressure Hormone | NYP