I have IBS normally, and it seems that as soon as I became pregnant I became constipated. After a couple of weeks of agony and trying natural home remedies I asked my ob and he said to take miralax. It worked wonders! I feel like a new woman and I'm enjoying my pregnancy for the first time since finding out.
make sure you are taking calcium and drinking about 60 oz of water and that will help. The calcium should have magnesium too and you can take 1000 mg every hour until you can go. Make sure you get a lot of fluids down first. Your colon will absorb all the calcium it needs and will send the rest for elimination which will cause a loose stool which is what you need.
Buy the orange flavoured Metamucil. Its high in fiber. Have a teaspoon in a glass of water once a day. It will change your life!! Safe for you and your bub.
Drink a glass of prune juice at night. And another first thing in the morning...