Hi Welcome to HEALTHCARE MAGIC.. I have gone through your query and can understand your concern... No birth control pill should not cause bleeding after intercourse & it should be related to sexual activity. The cause of vaginal bleeding in you must be bleeding from cervix (the lower part of uterus). Cervix has high blood supply & Even when cervix is healthy, mild trauma from vigorous sex can cause some bleeding. This mostly occurs when you have vaginal dryness or less vaginal lubrication. When you have vaginal dryness sex may feel painful & vagina may also feel tighter. You should use lubricants before having sex. Vaginal moisturizer would help to keep vaginal dryness away for longer period of time. However if vagina bleeding persists or re-occurs in you then it may need thorough investigation as It can be because of some abnormality in cervix. In case of cervix abnormality, even gentle sex in presence of enough vaginal lubrication could cause bleeding. Therefore repeatitive bleeding after intercourse could be a sign of cervix abnormality. Refer to a gynaecologist. Hope this information helps