Lipoprotein and phospholipid distribution in human follicular fluids

Human preovulatory follicular fluids, obtained in the course of stimulated cycles, were analyzed for their lipid and protein compositions. By combining different methods, a single class of lipoprotein, high-density lipoprotein, was detected in all cases. The phospholipid distribution revealed an accumulation of lysophosphatidylcholine. These data are discussed in view of the possible roles of the follicular fluid during fertilization and in relation to the high levels of estradiol and progesterone measured in those fluids.