Having a little bit of bleeding after intercourse at any point during a pregnancy can be normal. The rising levels of progesterone tends to make vessels enlarge and become more friable (easily traumatized). Sometimes during intercourse, a vessel on the cervix can be injured and may start bleeding. This will not affect or endanger your pregnancy. It is important, however, to notify your practitioner about any bleeding during your pregnancy and let him or her decide where it is coming from.