Pregnant women usually find they can't sleep as they they progress through their pregnancy.
There's the visits to the bathroom during the night. There's the hip pain and strain on the back, and the sheer difficulty getting comfortable in the bed due to the size and shape of the baby bump.
And these get more acute the later you are in your pregnancy.
There's not much you can do about the bathroom visits (other than try not to drink water late at night).