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Milk of Magnesia or other laxatives
We generally do not recommend laxatives for pregnant women, although providers may recommend them under special circumstances. (Some physicians recommend them sooner than others.)
We are cautious with laxatives because their regular use can make your intestinal system dependant on them. Of special concern during pregnancy, laxatives can cause intestinal cramping that may be hard to differentiate from preterm labor.
That said, you are not alone in dealing with constipation during pregnancy. Many pregnant women have it, to varying degrees, and we have several suggestions that may help relieve the problem.
Our first recommendation is to drink more fluids — about three quarts a day. Most of that should be water.
Fiber-rich foods also are good for reducing constipation. Eat more fruits and vegetables, whole-grain breads (check the wrapper for at least 3 grams of fiber per slice), brown rice, oat bran and beans (pinto, garbanzo, kidney and the like).
If you increase fluids and fiber in your diet and still have problems, then you can try a supplement, such as fiber pills (FiberCon is one example) or fiber powders (such as Metamucil) that can be mixed with liquid.
These steps will relieve most pregnancy-related constipation. However, if you still need help after these measures, try a stool softener, such as Colace. Stool softeners are available without a prescription.
If that also fails, talk with your provider about laxatives, including Milk of Magnesia. Yes, Milk of Magnesia is safe and will quickly fix the problem — but it isn't the best long-term solution during pregnancy for the reasons we described above. So, we prefer it far down the list of strategies.