Estradiol, progesterone and plasma lipids during the menstrual cycle.

Epidemiological data tend to relate some of the sex differences in plasma lipid levels to the physiological secretion of estrogens and progesterone. The influence of sex hormones on plasma lipoprotein metabolism has not been extensively investigated. Precise correlation between plasma lipids and circulating hormones levels are still lacking. The short term effect on plasma lipids of large variations in estradiol and progesterone plasma levels occurring during the menstrual cycle has been studied in eight fertile women over a total of 18 cycles. Concentrations of plasma lipids, particularly triglycerides and HDL cholesterol levels were remarkably stable in the three hormonal situations studied, namely during menstruation (low estradiol and progesterone levels), in the follicular phase of the cycle (high estradiol and low progesterone levels) and in the luteal phase (high estradiol and progesterone levels). Considerable variation of plasma estradiol levels (400%) did not modify, the plasma lipid values on a short term basis (8-21 days). The physiological role of 17-beta estradiol and progesterone in the sex differences of blood lipid levels remains to be clarified. If this metabolic effect exists, it does not seen to be influenced by short term variation in hormone levels.