I agree with what Nursegirl said. You need to talk to the prescribing dr to get her switched to Subutex. I would say to start a slow wean but I think that advice is best left to a medical professional. There is a little baby at stake here so I wouldn't make any move without the correct professional advice. You said shes on only 1 mg which is a very low dose as it is but still enough to cause withdrawals.
A psychiatrist is not the way to go...Id say get a joint plan from her primary dr. Let her be the coordinator between a new OBGYN and whatever dr prescribed the suboxone in the first place. They can formulate a plan that will allow you daughter to safely deliver your grandchild.
Good luck
God Bless you for being there for your daughter and helping her with this. Congratulations on the Grandbaby~ so nice to see you're looking out for them. Best of luck getting the help that you need.
She should be seeking another OB who is familiar with the drug. She also needs to let her sub doctor know that she is pregnant. Usually they will switch women over to Subutex, which is only the opiate, not the opiate blocker (naloxone).
Best to her!