Should we spill the beans?

I have had 5 chemical pregnancies and am pregnant again. This time I've made it further and even saw a heartbeat via US at 7 weeks (138).  Doc says everything looks good but she wouldn't tell anyone. With so many losses all of my amazing friends and family have been following my saga and already know. However my grandma will be in town for Easter which is also her birthday. I think it would be special to tell her face to face but worry it will be a disappointment if things go wrong again. What should I do?