Given a passage, construct a question on the basis of the information present in the passage. Construct the question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) it answer uses text phrases from the passage. Avoid creating questions that (i) can't be answered correctly without actually understanding the passage and (ii) uses the same words or phrases given in the passage.

The protective functions of oestrogen therapy alone on cardiovascular risk parameters are well established; however, the action of progesterone on vascular parameters in an oestrogen-deprived environment is less clear.', 'To examine the effects of progesterone alone on vascular function and hormone levels in postmenopausal women.', 'In a randomized, double-blind, cross-over design study, 20 healthy postmenopausal women were tested before and after 6 weeks of treatment with micronized progesterone (100 mg/daily) and matching placebo.', 'Tests included measurement of sex hormones and gonadatropin levels, lipids and measures of surrogate markers of vascular function including, blood pressure, flow-mediated dilation of the brachial artery, systemic arterial compliance and cutaneous vascular reactivity.', 'The mean (+/- SEM) age of subjects was 56.4 +/- 2.7 years and the average body mass index at the baseline visit was 27.1 +/- 1.0 kg/m2. Progesterone levels increased as a result of progesterone treatment (0.9 +/- 0.2 to 9.5 +/- 2.3 nmol/l, P = 0.001), whereas follicle-stimulating hormone levels decreased (75.1 +/- 11.4 to 67.6 +/- 10.0, P = 0.001). Systemic arterial compliance, flow mediated dilation, cutaneous vascular reactivity, blood pressure, body mass index, plasma levels of cholesterol, lipids and oestrogen were unchanged.
Does progesterone influence vascular function in postmenopausal women?