What does it mean when there are follicles in the uterus?

Don't be too excited or nervous when follicles are found in the uterus during examination. Generally speaking, as long as it does not affect people's normal life, no treatment is required, unless your follicles are found to have abnormal reactions during the examination. In this case, you can only find the specific cause, so as to judge the specific condition and cause of your illness and prescribe the right medicine.

a. Primordial follicle: close to the white membrane, with an egg cell in the center and a layer of flat follicle cells around it.

b. Growing follicles:

Primary growing follicle: one or more layers of cuboidal follicular cells, a red-stained transparent zone between the oocytes and follicular cells, and a connective tissue follicle membrane around the follicle.

Secondary growth follicles: Follicular cavities appear between the follicular cells. Some follicular cavities are very large, forming cumulus ovale. The follicular cells located on the inner wall of the follicle are densely arranged into several layers, called the granulosa layer. The follicle membrane can be divided into two layers: the inner membrane and the outer membrane.

c. Mature follicle: The follicular cavity is very large and the cumulus is very obvious. The follicular endometrial cells are close to the granulosa layer of the follicle and are separated from the granulosa layer cells by a basement membrane. The endometrial cells are polygonal, with clear cytoplasm and round nuclei. Many capillaries can be seen between the cells. The exometrial cells are located in the outermost layer, mostly spindle-shaped, and have no obvious boundary with the surrounding connective tissue. Corona radiata.

d. Atretic follicle: The structure of the egg cell is unclear or even disappears, the zona pellucida shrinks, and the follicle wall collapses.

The development of follicles begins with the primordial follicle. In each menstrual cycle, usually only one primordial follicle develops and matures under the regulation of hormones. The primordial follicle goes through the primary follicle and secondary follicle stages, and finally develops into a pre-ovulatory follicle (mature follicle). The primordial follicle develops into the early stage of primary follicle and is not controlled by pituitary gonadotropin.

Its development depends on the memory factors of the follicle itself. By the late stage of primary follicle development, FSH receptors appear on granulosa cells and LH receptors appear on endometrial cells. By the secondary follicle stage, the number of FSH receptors on granulosa cells further increases. Under the synergistic effect of estrogen, FSH induces the appearance of LH receptors in granulosa cells. As the follicles mature, the number of LH receptors on granulosa cells and endometrial cells continues to increase. From the primary follicle development stage, the follicle is controlled by pituitary gonadotropin, which promotes its development and maturation.

At the beginning of the follicular phase, the concentrations of estrogen and progesterone in the blood are at low levels, and the feedback inhibition on the secretion of pituitary FSH and LH is weak. The FSH in the blood shows a trend of gradually increasing, and LH also increases after one or two days. In the early 21st century, it was discovered that there is a protein in follicular fluid that promotes the secretion of FSH, called FSH-releasing protein, which may play a certain role in the increase of FSH.

In addition to the increase in FSH receptors, receptors for factors related to cell proliferation, such as insulin-like growth factor (IGF) and epithelial growth factor (EGF), also appear on the growing and developing granulosa cells of the follicle. Under the action of FSH and various growth factors, the granulosa cells develop and differentiate significantly, and produce aromatase, which can convert androgens (mainly androstenedione) produced by the endometrium and diffusely transported to the granulosa cells into estrogens. LH binds to the LH receptors on the endometrial cells and converts cholesterol into androgens through the cAMP-protein kinase system. Endometrial cells produce androgens, which are converted into estrogens in granulosa cells, a phenomenon known as the dual cell theory of estrogen secretion.