I feel your pain.... That said, I can find absolutely nothing that says it's safe during pregnancy. They are pregnancy category C which means they aren't sure if they are safe or not and at least in the last trimester can potentially induce labor.
Every site I found that suggested they may be safe was talking about just before labor and stressed talking to your doctor about it.
I think that possibly you may want to talk to your doctor about the Zofran to see if there are any other alternatives. I know for me personally, the constipation needs to be fought daily through use of Milk of mag and drinking lots of water. I cannot treat it as needed.
Best of Luck - Stephanie
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