Hi am 28weeks n four days..

After seeing my glucose tolerance test dox said everything is normal and she told to take urine culture once more.. So today after seeing result she told everything is normal and there is very very slight infection.. So suggested two tablets for a week..
Tab nitrofurantoin 100mg.(1-0-1)7days

Tab ranitin 150mg. (1-0-1)  5days..
Is it safe?? It won't harm baby right?