Knee Problems are making me uneasy about being PG

I am 25 and have had dislocation problems in my knee since I was about 11. I've had many x-rays, MRI's, and physical therapy to help the problem. It has happened to me while working 4 times and I've have to take an ambulance 2 of those times. Now it seems to happen at least once a year. When I was younger it happened every few months. It is the absolute worst feeling in the world. I am afraid of walking in the mall, because it has happened when I was just simply walking down a hall. I am more afraid of doing something I have always wanted and that is to have a child. I am nervous that it will happen and I could land on my stomach or be carrying an infant and it happen. Has anyone with this problem been ok being pregnant with this problem?

Pam