Bleeding after BM

Hello ladies. I have chronic constipation and can not take my Medication while pregnant. Anytime I have a BM, I have to strain and I have vaginal bleeding. My old doctor didn't seem to think it was a big deal but I switched doctors after my miscarriage and haven't been able to talk to my new one since finding out. I drink a lot of water, take fiber supplements, and go on long walks so I'm doing all I can but having my condition and being pregnant really takes a toll. Has this happened to anyone else?