Variations in serum lipids and lipoproteins throughout the menstrual cycle.

One hundred fourteen women of reproductive age were included in a cross-sectional study with the aim of establishing the variations in serum lipids and lipoproteins during the menstrual cycle. Total cholesterol, triglycerides, and phospholipids were determined in whole serum and in the following lipoprotein fractions: very low-density lipoproteins (VLDL), low-density lipoproteins (LDL), and high-density lipoproteins, obtained by ultracentrifugation. A significant decrease was found in total cholesterol (P less than 0.05) and phospholipids (P less than 0.01) during the late luteal phase. The LDL cholesterol decreased during the luteal phase and VLDL cholesterol increased in the early and midluteal phases. The LDL phospholipids and VLDL triglycerides also showed a significant decrease during the luteal phase (P less than 0.01). The results of this investigation demonstrate major fluctuation in cholesterol, triglyceride, and phospholipid-lipoprotein composition during the menstrual cycle.