What causes bleeding after sexual intercourse?

There are numerous causes of vaginal bleeding. Bleeding after sexual intercourse is clinically termed “contact bleeding.” Typically, contact bleeding involves only a small amount of blood, which is usually light red or sometimes brownish in color. It is important to promptly investigate the underlying cause of postcoital bleeding and initiate targeted treatment. So, what exactly causes bleeding after intercourse? Below, we address this question.

What Causes Bleeding After Intercourse?

1. Cervical Cancer

Cervical cancer lesions contain abundant fragile capillaries; thus, minor trauma during intercourse may cause these vessels to rupture, resulting in bleeding. Cervical cancer is the most common gynecologic malignancy. The progression from HPV infection to precancerous cervical lesions and ultimately to invasive carcinoma typically takes approximately 10 years. Recognizing early symptoms of cervical cancer facilitates timely detection and effective treatment.

2. Cervicitis

Cervicitis is classified as mild, moderate, or severe based on the extent of cervical ectropion (formerly termed “cervical erosion”). In cases of moderate-to-severe ectropion, friction between the male partner’s glans penis and the cervix during intercourse may cause mechanical injury and subsequent bleeding. Because the volume of bleeding is generally small and does not occur immediately, blood may accumulate within the vagina. Over time, fresh blood oxidizes and darkens, appearing as dark red discharge the following day. Additionally, endometrial hyperemia and edema may occasionally lead to postcoital endometrial bleeding, though this is relatively uncommon.

3. Vaginal Laceration

Vaginal laceration may occur during first-time intercourse due to hymenal rupture, typically resulting in immediate, minimal bleeding that stops spontaneously. However, if vaginal bleeding occurs during or shortly after intercourse—especially if it is profuse, persistent, and fails to stop spontaneously—it likely indicates a vaginal laceration. Such injuries may result from incorrect or overly forceful sexual techniques, causing tears or trauma to the vaginal mucosa. Vaginal lacerations may also be associated with congenital vaginal anomalies, such as longitudinal or transverse vaginal septa or double vagina.

The above outlines the potential causes of postcoital bleeding. We hope this information is helpful to you.