How to tell boyfriends family about my pregnancy

My boyfriend and I have been together for almost 4 years we've been staying together for 7 months and I'm 9 weeks pregnant I was recently laid off from my job but have a job lined up for me to start hopefully in the next 2 weeks. I kind of want to wait to tell them until I start the job but seeing as though I'm very sick I don't think I can hold it much longer. His concerns are he doesn't want to disappoint them and my concerns are that his mother is very opinionated and I don't think I'll be able to shut my mouth if she has anything negative to say. It's their first grandchild so I don't want it to be through text but I don't want to be there for the backlash of it all. But what are some suggestions you all have I'm posting anon so I won't be replying but I appreciate all the input