My period came on the 12th last month. When will it come this month?

A complete physiological cycle starts from the first day of menstruation until the first day of the next menarche. Under normal circumstances, the menstrual cycle is measured in months, but in reality it varies from person to person. The calculation of menstrual cycle should include the time of menarche. Some women only calculate the time when the menstrual period ends, which may make them feel that the menstrual cycle is shortened. A menstrual cycle is generally 21-35 days, with an average of 28 days. It is normal to have menstruation once at the beginning and end of each month.

How do you know if your menstrual cycle is normal? The length of menstrual cycle varies from woman to woman. It is within the normal range if the menstrual cycle is 7-10 days earlier or later. As long as the menstrual cycle is maintained at a certain regularity, it is not considered as irregular menstruation.

The physiological cycle is also called the uterine and ovarian cycle, which is divided into four stages, including the follicular phase, ovulation phase, follicular phase and physiological phase:

1. Follicular phase: The follicular phase is from the first day of menarche to ovulation. During this period, under the influence of follicle-stimulating hormone, the body's estrogen and testosterone concentrations increase, the follicles gradually mature, and the endometrium thickens.

2. Ovulation period: Ovulation period refers to the whole process of the egg and the surrounding cumulus granulosa cells being discharged together. Women's ovulation period is generally about 14 days before the next menstrual period.

3. Follicular phase: The follicular phase refers to the period from ovulation to the day before menarche. The uterus and ovaries are affected by luteinizing hormone, which metabolizes luteinizing hormone to maintain the thickened uterine wall to facilitate the combination of sperm and egg and implantation. If there is no sperm and egg, the uterine wall will dissolve, and the physiological cycle ends with the menarche.

4. Menstrual period: The duration of each menstrual period is called the menstrual period, which is generally 2-8 days, with an average of 4-6 days. Generally, there are no special symptoms during menstruation, but due to pelvic congestion and the effects of prostacyclin, some women may experience a feeling of heaviness in the lower abdomen and lumbar region or uterine contraction pain, and may also experience gastrointestinal disorders such as diarrhea.