Working away from home advice

Work in a specialised tech field. Have just been informed that I am now going to be required to work away 1-2 weeks a month due to insufficient work load as opposed to previously just going away when needed maybe 4 weeks a year.

Can I just refuse? When I was hired I was told I’d only need to travel for training and as previously mentioned only when absolutely needed to help out in other states. I will be going through my employment contract but it’s a very large company so I’m sure they would have something in there to protect themselves.

They hired me knowing the work load wouldn’t be available to me for some time so I don’t feel like it’s fair for that to fall onto me to the point of me having to change my lifestyle to suit. I’m also looking to start a family this year so going away that often is just not an option.

Will be discussing with my manager early next week, just searching for any advice TIA