A woman’s follicles are not round, but oval or nearly so. The shape of a woman’s follicles is mainly related to the amount of follicular fluid in the woman’s follicles, as well as follicular tension. A woman’s follicle contains follicular fluid and an egg, but the egg is so small that it cannot be seen by ultrasound or with the naked eye, only the follicular fluid inside the follicle. The follicle is subjected to pressure from the ovarian peritoneum as well as the surrounding tissues, and this pressure, along with the tension created by the follicular fluid, works together to keep the woman’s follicle in a stable shape. If the external pressure is high and the tension is low, the follicle tends to be flatter and oval, and conversely a woman’s follicle will be more round. The closer a woman’s follicles are to being round, the better the follicular tension is, and the better the quality of the woman’s eggs.