What is the average length of a menstrual cycle?

The average length of a menstrual cycle is widely considered to be about 28 days. This standard is based on the typical hormonal and physiological changes that occur within the female body. A menstrual cycle begins on the first day of menstruation and lasts until the start of the next period.

During this cycle, various phases occur: the follicular phase, ovulation, the luteal phase, and the menstrual phase. The cycle is influenced by hormones such as estrogen and progesterone, which prepare the body for potential pregnancy. While individual cycles can vary significantly, with some women experiencing shorter or longer cycles, 28 days remains the most commonly cited average.

Understanding the average length is important for tracking fertility, menstrual health, and planning for contraception or pregnancy. It also helps individuals recognize any irregularities in their cycles, which may warrant further exploration with a healthcare provider.