Keeping the secret!

My boss and co-workers spread gossip like crazy - even when I have requested to my boss that I would like things keeping strictly confidential. I’m currently on holiday and just found out I’m 6 weeks. I really don’t want our news to become office gossip before we tell our family (at 12 weeks). However, I’m worried that I will struggle to keep the secret at work if I get sickness and I know that for my own safety I should probably share my news.

Thoughts? Advise? Anyone had a similar issue?