Cysts and pregnancy...

Emily • Mrs 3/21/15 Mama 3/31/16 Due with #2 May 2019
I went to my first ultrasound today and they found a huge cyst on my ovary. The baby had a great heartbeat of 161 and looked to be completely on tract measuring 7 weeks 3 days. But I was just wondering of any experiences with cysts like that and pregnancy? I have to go back in 4 weeks for them to look at it again and they said if I have any bleeding or excruciating pain to call them... TIA