Pregnant after four miscarriages

Hubby and I have been TTC or second child for over two years. During our time we’ve had four miscarriages and had seen specialists but got no answers as to why we are struggling. I had honestly given up on the thought of trying after my last D&C. Went to the doctor finally after feeling sick and found out we are pregnant again, this appointment was a lot different than the last 4 because I we got to see the baby and a very strong heartbeat. 7w1d ultrasound. Due 4/17/2019