Dear suzan,
try this it worked for me.
put a surveillance camera(s) in your house and tell your helper frankly that you'll be monitoring her by recording her activities with your baby, NOT because you don't trust her BUT because you wanna know if something wrong happened and she didn't react in a right way so you can Teach her how to take better care of your baby.

you can actually record on a DVD recorder or NOT, most of them aren't that electronically educated to know the difference.

or else try to buy the internet camera through Qtel, it's a good one if you have access to internet in your work.
I feel with you, our babies are the most important thing in our lives and we can't imagine someone would harm them.

on the other hand, choose your helper wisely, go to a well known office and try to contact her before she arrives to qatar and tell her what you expect from her so she won't be surprised when she's in your house.

Spot checks visits to the house during the day (irregular timing) would help as well.

Best luck

Yalla!