First of all it would be best to check with your OB/GYN to make sure you are not harboring an infection. You can treat this naturally! Which would mean there would be no harm done to your pregnant body or baby.
Using a scented pad will cause infection so can commercial soaps and powders. Use alternative natural means whenever possible!
Sometimes what can happen when you are pregnant is an increased discharge, it is quite normal. It can also be quite normal to notice a smell. But if you are concerned check with your doctor. Just don't use pharma products.
You could also check with a naturopathic physician for alternative treatments that are safe for pregnant women.