What does the number of days in the menstrual cycle mean?

As women age, their bodies begin to mature. After puberty, the endometrium begins to be affected by hormones in the ovaries and regular, periodic bleeding occurs, also known as menstruation. The menstrual cycle is generally 28-30 days, and the duration of menstruation is generally around 3-7 days. Depending on each person's physical condition, the menstrual cycle may be easily delayed.

Menstrual cycle

After women enter puberty, the endometrium is affected by ovarian hormones, causing periodic uterine bleeding, which is called menstruation. The cyclical changes in the endometrium are called the menstrual cycle, which is also the human reproductive cycle.

Physiological mechanisms

The time between the first days of two menstrual periods. Most of the time it is 28 to 30 days, and 3 days earlier or later is within the normal range. The length of the cycle varies from person to person, but each woman's menstrual cycle must have her own regularity, otherwise it should be considered abnormal. The menstrual cycle is regulated by the interaction between the hypothalamus, pituitary and ovaries. The hypothalamus regulates the function of the pituitary gland, which in turn regulates the function of the ovaries. The endometrium undergoes cyclic changes under the action of ovarian hormones. The sex hormones produced by the ovaries in turn act on the hypothalamus and pituitary gland, affecting the release of gonadotropin-releasing hormone (Gn-RH), follicle-stimulating hormone (FSH) and luteinizing hormone (LH), which is a feedback effect. When its release is inhibited, it is called negative feedback, and when it is promoted, it is called positive feedback.

After the corpus luteum atrophies in the first menstrual cycle, the secretion of estrogen and progesterone decreases, relieving the inhibition on the hypothalamus and pituitary gland. Gn-RH produced by the hypothalamus promotes the secretion and release of FSH and LH. Under the synergistic action of FSH and LH, the follicles in the ovaries gradually develop and mature, and the production of estrogen causes proliferative changes in the endometrium. After the follicles mature, the first peak of estrogen appears in the body. Increased estrogen secretion inhibits the production of FSH, promotes increased LH secretion, causes an LH peak, and triggers ovulation. After ovulation, the corpus luteum is formed and secretes estrogen and progesterone. Under their combined action, the endometrium undergoes typical secretory phase changes. After ovulation, estrogen levels temporarily decrease, followed by a second, lower peak. The large amount of estrogen and progesterone secreted by the corpus luteum reduces the secretion of FSH and LH through negative feedback, and the corpus luteum begins to atrophy. Subsequently, the secretion of estrogen and progesterone decreases, the endometrium loses the support of sex hormones, necrosis and shedding occur, and menstruation occurs. After the corpus luteum atrophies, the inhibition on the hypothalamus and pituitary gland is released, and Gn-RH is secreted again to start another menstrual cycle.

What does menstrual cycle length mean?

There are many reasons. Some women have a long menstrual cycle due to physical reasons, which is normal.

1. Emotional reasons. If a woman tolerates abnormal emotions for a long time, sulks, or suffers from stimulation and psychological trauma, it may lead to long menstrual cycles or dysmenorrhea or amenorrhea.

2. Excessive dieting to lose weight. Expert research shows that girls need body fat to account for at least 17% of their body weight before they can have their first menstruation, and body fat must account for at least 22% of their body weight to maintain a comfortable menstrual cycle. Therefore, women who pursue a slender figure should never believe in dieting lightly. If it affects the body and causes a long menstrual cycle, it will not be worth it.

3. Addicted to bad living habits such as smoking and drinking. Certain components in tobacco smoke and alcohol can interfere with the physiological processes related to menstruation, which is the reason for prolonged menstruation. Among women who smoke and drink excessively, 25%-32% go to the hospital for treatment due to irregular menstruation. Therefore, women should not smoke and drink less alcohol.