just make sure it's a softener not a laxative and if you take it every three days and it's still difficult then do every other day till it is easier...
try taking a stool softener every 3 days that will help just make it easier it won't make you go more it will just make it easier...pregnancy causes constipation in many women and if your straining you can cause hemriods...not that you want to hear that but I hope it helps because as you get farther along it can cause more issues