While lots of women complain about being stopped up during pregnancy, the opposite can happen too — though not as often, and it generally doesn't last as long. Medically defined as loose (or watery) and unusually frequent bowel movements, diarrhea is definitely one of those "you'll know it if you have it" pregnancy symptoms.

Here's everything you need to know if you're experiencing diarrhea during pregnancy, including the best ways to safely treat it.

What causes diarrhea during pregnancy?

Unlike constipation, which can be caused by pregnancy's fluctuating hormones, diarrhea tends to be caused by something that originates outside your body — and something that's not necessarily harmful either.

Diarrhea may be the result of all that good-for-you food you're now eating, the extra water you're drinking or even the workouts you've begun. It can also happen right before going to labor, as your muscles loosen and prepare for childbirth.

Some women find that their prenatal vitamin causes loose stools; changing brands can sometimes make all the difference.

That said, there are things that can cause diarrhea during pregnancy that have nothing to do with hormones or lifestyle changes. Food poisoning, intestinal parasites or a simple stomach flu may be behind a nasty bout of stomach bugs during pregnancy. If you suspect any of these might be the case, call your practitioner ASAP so you can be tested and treated.

Remedies for diarrhea during pregnancy

Avoid certain foods

Keep away from foods that could make the problem worse: dried fruits (consider prunes your enemy); fatty or spicy foods; and milk, especially if you're lactose intolerant. The so-called BRAT diet (bananas, rice, applesauce, toast) has been recommended for years because it’s gentle on your digestive system and can help make stools firmer and more solid.

However, the newest thinking expands on those options to include other important vitamins and minerals (especially zinc) that are not provided by the BRAT diet. Try adding the following: 

  • Other starchy foods like potatoes, unsweetened cereals and crackers
  • Cooked vegetables including carrots, peeled zucchini, green beans, beets and acorn squash
  • Non-milk-based soups with vegetables
  • Lean meats
  • Cooked eggs
  • Yogurt, especially with live, active cultures of lactobacillus acidophilus 

Also be sure to avoid eating a few foods that can make diarrhea worse:

  • "Simple" high-sugar drinks (apple and grape juice, gelatin, regular colas and other soft drinks), which can draw water into your tummy, making diarrhea last even longer
  • Fatty and fried foods
  • Gas-causing fruits and vegetables, such as beans, broccoli, peas, prunes and chickpeas
  • Dairy products, if they're causing gas or other intestinal upset

Drink plenty of water

Also key? Staying hydrated — which is important throughout your pregnancy, but especially when diarrhea strikes. The recommended amount varies based on your body type and size, and how active you are, but aim for eight to 10 8-ounce glasses of water (from all sources) a day.

Ask your doctor about sipping a sports drink with electrolytes, which can replenish lost fluids plus key minerals like sodium, chloride and potassium.  

Ask about medications 

Always check with your doctor before taking any over-the-counter diarrhea medications. And of course, if you’re on a stool softener for constipation in pregnancy, be sure to stop taking it until your stools return to a normal consistency.

When to call your doctor

Remember, while a mild case of diarrhea isn't anything to really worry about during pregnancy, there are a few times you should get in touch with your practitioner right away, including if you:

  • Have more than three stools a day
  • Have diarrhea lasting more than 48 hours, despite dietary changes
  • Have stools that are bloody, contain mucus or are purely liquid
  • Were recently in close contact with someone known to have a parasite or stomach flu
  • Suspect that your diarrhea is a sign that you’re in labor
Diarrhea that persists for more than a couple of days, no matter how mild, is worth a call to your practitioner: It’s not only a pain in the rear, but it can also quickly lead to dehydration, a major risk factor for premature labor. For that reason alone, if you've got it, take it seriously.