Hi,
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Bleeding during foreplay or intercourse could be suggestive of rupture of hymen, vaginal injury (if pressure is rough), vaginal or cervical infections, severe PID, cervical dysplasia etc. You should consider visiting a gynecologist for a thorough internal examination, vaginal swab/smear test and a PAP smear test to confirm the cause for the bleeding. Appropriate treatment would be started to help you control the symptoms. Maintain good hygiene. Make sure your partners hands are well washed (and nails neatly trimmed), and you remain in the comfort zone during the foreplay or intercourse.
Take care.