How Often Is It Normal to Have a Menstrual Cycle?

Generally, a woman's menstrual cycle ranges from 28 to 32 days. However, due to individual differences, the length of the menstrual cycle can vary from person to person. A variation of approximately one week earlier or later is considered within the normal range, and as long as a certain regularity is maintained, it cannot be considered menstrual irregularity.

The menstrual cycle is calculated from the first day of the current menstrual period to the first day of the next menstrual period. The calculation of the menstrual cycle should include the time of menstruation. For example, if the first day of the most recent menstrual period was September 31st, and the first day of the previous menstrual period was September 1st, the difference between these two dates is 30, indicating a menstrual cycle of 30 days.

During menarche, as the ovaries are still developing and their functions are not yet fully developed, there may be functional disorders and irregularities, leading to abnormal menstrual cycles. This is normal and does not require concern. As age increases, the ovarian function gradually matures, and the menstrual cycle will become more regular.

If menstruation occurs earlier or later than expected by more than 7 days, it is considered a delayed menstruation. The reasons for delayed menstruation may include pregnancy, as well as factors such as medication, mental state, illness, lifestyle changes, or changes in living environment that may affect the menstrual cycle. For women who have had normal menstruation and are sexually active, a 10-day delay in menstruation may indicate pregnancy. In this case, a self-administered pregnancy test or a blood HCG test at the hospital can be used to confirm pregnancy.

Menstruation can provide signals for identifying women's physical condition, so it is necessary to understand the main reasons for delayed menstruation.