How many follicles are there on the third day of menstruation?

Menstruation is the normal physiological cycle of every female body. There are no follicles after the end of menstruation. Therefore, the period after menstruation is a safe period for women. The chance of pregnancy during this period is small. Smaller follicles begin to grow in the uterus on the 8th to 9th day. They will gradually mature over time. Finally, when the woman reaches the ovulation period, the chance of pregnancy during intercourse is higher.

How many follicles are there on the third day of menstruation?

On the third day of menstruation, there are usually no follicles in the ovaries. Small follicles begin to appear on the 89th day and reach a diameter of about 10 millimeters on the 10th day. It matures on the thirteenth or fourteenth day, and the mature follicle is generally larger than eighteen millimeters. It means ovulation is approaching.

Follicular phase

The follicular phase starts from the day the last menstrual period stops and ends on the day of ovulation, lasting 10 to 12 days. During this stage, the granulosa cells of the follicles produce estrogen under the action of FSH and LH. Under the action of estrogen, the endometrium proliferates rapidly, blood vessels proliferate, and the glands widen and lengthen, but no secretion occurs.

At the end of this period, the ovary releases an egg. If the egg matures but cannot be released for some reason, it will enter the next stage. Women should buy a basal thermometer or a smart thermometer and master the reading method to ensure accuracy.

Categorical features

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.

Growth process

The development of follicles begins with the primordial follicle. During 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 early stages of the development of the primordial follicle to the primary follicle are not controlled by pituitary gonadotropin, and their development depends on the internal 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.