Velamentous Cord insertion

Nicole
I just had my anatomy scan today (18w4d). I'm a high risk pregnancy due to age and its twins. We were told today that baby B is measuring about 9 days behind schedule but Baby A is doing well - they are di-di twins. Baby B has velamentous cord insertion. 
Has any one else had experience with this issue?
We are told it's basically a watch and see/ monitor sort of situation, and we can't really do anything about it. My husband and I are freaking out a little and researching.
Thanks for sharing anything helpful!