Simple explanation
The menstrual cycle is the body’s repeating pattern of preparing for a possible pregnancy. If pregnancy does not happen, the lining of the uterus comes away as a period.
Cycle length varies
Many people hear that a cycle is 28 days, but cycles can be shorter or longer. Some variation is common, especially in teenagers, after pregnancy, during stress, and approaching menopause.
Hormones and symptoms
Hormone changes across the cycle can affect bleeding, discharge, mood, energy, skin, sleep and appetite. Tracking patterns can help people understand what is typical for them.
When to seek advice
Ask for medical advice if cycles are suddenly very different, bleeding is very heavy, pain is severe, or periods stop unexpectedly and pregnancy is not the reason.
Helpful next step
Prepare for an appointment