What are the causes of itchy, painful bumps after sex?

Question

Hello doctor,

After having sex with my girlfriend while she was on her period, I developed small bumps that were itchy and occasionally painful. I got tested for STDs, and the results came back negative.

What could it be? This only happened once and did not occur during previous instances of sexual intercourse while she was menstruating.

Please advise.

Answer 1

Hello,

Welcome to icliniq.com.

Thank you for providing detailed information; it really helps narrow things down.

Based on the following:

You had sex with your girlfriend while she was on her period.
You developed small, itchy, and occasionally painful bumps afterward.
STD (sexually transmitted diseases) testing came back negative.
This has not happened during previous sexual encounters, including period sex.

Here are some possible explanations for your symptoms:

Irritant contact dermatitis: This is one of the most likely causes. During menstruation, the vaginal environment changes (pH shifts, blood can be mildly irritating), and if there was prolonged friction, latex condoms, or exposure to menstrual blood without protection, your skin may have reacted with inflammation or irritation.
Friction-induced folliculitis or razor burn: If you shaved recently, friction during intercourse, especially with moisture and heat, can inflame hair follicles or cause tiny abrasions that lead to bumps or itching. Sometimes, sweat and bacteria trapped in hair follicles can cause small, painful pustules.
Non-STD viral or bacterial skin infection: Even with negative STD results, skin-to-skin contact can transmit other infections, such as molluscum contagiosum (small, firm, smooth bumps), herpes simplex virus (though your test came back negative, early-stage herpes or non-lesion-based testing might miss it), or staph or MRSA (methicillin-resistant staphylococcus aureus); these bacterial infections can cause painful, red, and sometimes pus-filled bumps.
Allergic reaction: Some individuals have sensitivities to latex condoms, lubricants, or menstrual hygiene products (scented tampons or pads). An allergic reaction could explain localized irritation, especially if these products were used during menstruation.

What you can do:

Consider seeing a dermatologist or urologist for a visual examination if the bumps return.
Keep the affected area clean and dry; avoid using harsh soaps or irritating products.
Try non-latex condoms if you suspect a latex allergy.
Avoid shaving before sex to reduce the risk of skin irritation.
Keep a log of any recurring symptoms, including timing, products used, and any physical changes.

I hope this helps you.

Thank you.