What is the reason for vaginal bleeding seven days after menstruation?

Patient's question:

My menstrual cycle has always been very regular, but recently for the past two or three months, there has been a small amount of blood flow around the seventh day after my period ends, similar to the last day of my period when it's about to finish. What could be the reason for this? Please answer, thank you

Doctor's answer:

Hello, it is possible that it is ovulation bleeding.
During the mid-cycle, i.e., the ovulation period, due to a temporary decline in estrogen levels, the endometrium loses hormonal support, leading to partial shedding of the endometrium and causing regular vaginal bleeding, which is referred to as ovulation bleeding. In traditional Chinese medicine, it is called "intermenstrual bleeding."
Treatment
1. Western medicine treatment: Diethylstilbestrol 0.25–0.5 mg per day, starting 3 days before ovulation and stopping 2–3 days after the bleeding stops.
2. Traditional Chinese medicine treatment: Liuwei Dihuang Wan, Gujing Wan, and Xuefu Zhuyu Wan.
Prevention and Care
1. Pay attention to menstrual health, maintain external genital hygiene, and prevent pelvic infection.
2. Keep a calm mood and avoid excessive stress.