After the menstrual period, it came again a week later. What's going on?

Patient's question:

Duration of illness and persistence: Once, a few days
Detailed condition and purpose of consultation: Had sexual relationships before, took birth control pills
Current general condition: Menstruating
Medical history: None

Doctor's answer:

Hello, it should be ovulatory bleeding. This occurs because during the ovulation period, the follicle ruptures, and after ovulation, the estrogen level drops, unable to maintain the normal growth of the endometrium, leading to a breakthrough bleeding phenomenon of the endometrium. The amount of blood is similar to that of menstruation, and it generally does not exceed one week. As long as there are no obvious abdominal pain or other discomfort symptoms, no treatment is needed.