I was really nervous about this issue as well. I absolutely love my doctor and I was so worried that she would feel slighted in some way if I asked to talk to someone else as well. When I brought it up, she actually said that if I ever ran into a doctor that had a problem with someone getting a 2nd opinion, I should be worried. So, I had an appt with the regular peri (delivered my son) and then with a peri at a teaching hospital that I had never seen before. They did have a difference of opinion on when to start the baby aspirin. I just recently saw my regular doctor again and the 1st thing she did was ask about my appt at UCLA. She was very interested in what they had to say and, we agreed to follow the aspirin schedule that the 2nd opinion peri recommended. All worked out very well. My doctor was not upset at all that I #1 requested to see someone else and #2 will follow their recommendation on the aspirin. I think she is just very happy that we're doing everything we can prior to conception to prepare. As if I'll ever be "prepared"...
I do think you should tell them about your 2nd opinion, you may find that they end up agreeing or, at least share with you why they don't so that you can make the most informed decision for yourself.
Good luck and let us know how it goes!
Zachary James, 7/22/03-7/27/03, born at 26wks - severe pe