Bleeding after sex (called postcoital bleeding) is fairly common, and causes range from minor irritation to infections or, rarely, something more serious. It is important to pay attention to how much you are bleeding, how often it happens, and whether you have pain or other symptoms, and to see a clinician promptly if you are at all concerned.

Common benign causes

Light bleeding or spotting after sex often comes from irritation of sensitive tissues in the vagina or cervix. This can happen from friction (not enough lubrication, long or rough intercourse, certain positions, larger partner), small tears in the vaginal tissue, or normal uterine bleeding if sex happens right as a period is starting or ending. Vaginal dryness from hormonal changes (birth control, breastfeeding, menopause, some medications) can also make tissue easier to tear and bleed.

Infections and inflammation

Infections are a very common cause of bleeding after sex. Sexually transmitted infections like chlamydia and gonorrhea, as well as cervicitis (inflamed cervix), pelvic inflammatory disease, yeast or bacterial infections, and genital sores (for example from herpes) can all inflame or damage tissue so it bleeds more easily during sex and may also cause unusual discharge, burning, or pelvic pain. These usually need evaluation and treatment (often antibiotics or antivirals) to prevent complications and to protect partners.

Growths, hormones, and devices

Noncancerous growths such as cervical or uterine polyps and fibroids, or conditions like cervical ectropion (when delicate cells from inside the cervix extend outward) can bleed when touched during intercourse. Hormonal birth control and blood‑thinning medicines can change bleeding patterns, and an IUD that is out of position or irritating the cervix or uterus can also cause postcoital bleeding.

When it can be serious

Less commonly, bleeding after sex can be a sign of precancer or cancer of the cervix, vagina, or uterus, especially if you are over 35, postmenopausal, or have not had regular cervical screening. Heavy bleeding, bleeding that happens often, bleeding after menopause, or bleeding with pelvic pain, foul or unusual discharge, fever, or pain during sex warrant urgent medical evaluation or emergency care, depending on severity.

What you should do now

Because bleeding after sex has many possible causes and some need prompt treatment, it is safest to contact a healthcare provider or urgent care as soon as you can, especially if this is new for you, is more than very light spotting, keeps happening, or you have pain, discharge, fever, or pregnancy is possible. Until you are evaluated, avoid further intercourse or use lots of lubrication and gentle positions if you do have sex, and seek emergency help immediately if you soak pads, feel dizzy or faint, or have severe pain.