How long have you known that she is expecting?
If she seems to be swollen,and her nipples are heavy,I would find a quiet room to isolate her in,so she will have peace and quiet.I tried this,with Pouncette the Starry Cat,but she ran downstairs and had her Babies in My LP Storage Case.
I heard meeews,and there they were with thier Momma Cat.
I took them into the Spare bedroom,and closed them in.
They are all adopted now,and doing fine.
Good Luck with your Momma Cat,and her Babies!