I've volunteered through work to help with a shift supporting Ukrainian refugees arriving at the local airport tomorrow afternoon. I found out I'm pregnant this week and now I'm a bit worried about being out in a crowd of people with Covid cases rising. My first pregnancy was 2 years ago in lockdown so I don't know what risks are normal in pregnancy. Would it be unreasonable to ask to cancel my shift? It's a massive company so there loads of people going.