Prometrium oral vs vaginal suppositories

After two early miscarriages in a row my doctor decided to do blood work every two days starting with a positive pregnancy test. Everything was going fine until my progesterone dropped significantly so he decided to put me on prometrium oral 100mg 2x daily. The side effects for me are almost unbearable extreme dizziness, fatigue, and just feeling out of it so much that I don't feel comfortable driving.

Anyways the question is are there less side effects of the suppositories? Also are the suppositories as effective at raising progesterone levels.