What is the reason for bleeding after cohabitation?

Patient's question:

Patient Age: 35
Detailed Condition and Purpose of Consultation: Irregular menstrual bleeding
Duration of Current Illness: 4 months
Current General Condition: Bleeding after intercourse
Medical History: Mid-cycle bleeding for 3 years (with light flow), recently having 3-4 episodes of bleeding per month (but bleeding after intercourse, with light flow).
Previous Diagnoses, Treatments, and Outcomes: Western medicine and traditional Chinese medicine regulation for 2 months, ineffective.
Ancillary Examinations: Ultrasound showed normal results, colposcopy showed normal results, blood flow was from the cervical os.

Doctor's answer:

Hello, female sexual intercourse bleeding. First, it is necessary to identify the cause of the bleeding. If the sexual intercourse bleeding is caused by local organic lesions of the female external genitalia, curing the local lesions can also cure the sexual intercourse bleeding. If the sexual intercourse bleeding is caused by vulvar ulcers, vulvar eczema, or vulvar herpes, antibiotics should be used first to eliminate inflammation and cure the eczema and herpes, naturally curing the sexual intercourse bleeding. If the sexual intercourse bleeding is caused by vaginal trichomoniasis, trichomoniasis should be treated first. After the trichomoniasis is cured, the sexual intercourse bleeding will naturally subside.
For bleeding caused by improper sexual intercourse, couples should learn about sexual knowledge together, be considerate of each other, cooperate fully, and relax mentally. They should also appropriately restrain sexual activity. Sexual intercourse should be prohibited during a woman's menstrual period, and the possibility of malignant lesions of the reproductive organs should be. Once the phenomenon of bleeding after sexual intercourse occurs, it is necessary to go to a regular hospital's gynecological department for related examinations such as colposcopy and ultrasound to confirm the diagnosis and then treat it, in order to avoid delaying treatment due to procrastination.