Cholesterol levels vary with the menstrual cycle

A study recently published in The Journal of Clinical Endocrinology & Metabolism proves that we must take the menstrual cycle into consideration when testing cholesterol in cycling women.

"The objective of the study was to evaluate the association between endogenous [internally produced] estrogen and serum lipoproteins across the menstrual cycle."

The authors found that total and LDL cholesterol were lower during the luteal phase (second half, when progesterone is higher) than the follicular phase:

"More women were classified above the desirable range (LDL ≥130 mg/dl or total cholesterol ≥200 mg/dl) when measured during the follicular phase [first half]."

HDL was higher when estradiol had peaked, corresponding also to lower LDL and triglycerides.

"Because lipoprotein cholesterol levels vary across the menstrual cycle, cyclic variations in lipoprotein levels may need to be considered in the design and interpretation of studies in reproductive-age women and in the clinical management of women's cholesterol."