The basal follicle, also called the primordial follicle, is present in the ovary from the embryonic period and is composed of an oocyte and a rhombic or flattened cell. The basal follicles are atretic until puberty, when they begin to develop with the onset of menstruation and the secretion of hormones in the body, and each month a group of basal follicles will develop into growing follicles. If the hormone level in the body is normal, the growing follicles will develop into mature follicles and ovulate around the 14th day before the next menstrual period, and there will be growing follicles in both ovaries, and the number of follicles in each side is different. In order to promote the development of basic follicles in the body, it is recommended to eat more foods with high estrogen content, such as milk, eggs and beans.