Working while pregnant

I work in a restaurant as a supervisor, I do shift work, lately they’ve been putting me on late shifts so from 3 til close, which could be 11/12pm..every day last week. It’s messing with my sleeping patterns and I end up spending most of the next morning in bed trying to catch up. And now they’ve put me on 2 12 hour shifts in a row.

I’m 13 weeks pregnant, which they know but I feel like they don’t care about my welfare?

We had a previous manager who was pregnant and they didn’t go easy on her, put her in long hours, she ended up having real problems and going on mat leave early.

I’d have thought they learned their lesson from last time.

I know it doesn’t seem like a big deal but I just feel really let down. They don’t seem to realise that i have to take care of myself now.

Not sure how to approach the situation

Any advice would be great