I' ve been married for 6yrs and have almost always bled after sex. I was so frustrated I mentioned it to my GP when I had a pap and he said I had an STD. Which I knew was not possible, because my husband and I had only been with each other & waited until marriage. Anyway, long story short- I ended up seeing an ob/gyn and she thought I had endometriosis so I had a laparoscopy and she was right. Sex was also painful for me. I have 2 kids now and sex is still painful but I only randomly spot or bleed after. Last time I bled pretty heavy, heavy enough for my husband to ask if I had my period.

Also, make sure you're using plenty of lube