Causes of Diarrhea in the First Trimester of Pregnancy

Defined as loose or watery and frequent bowel movements, diarrhea is a common woe for pregnant women. There are a number of things that can cause diarrhea during the first trimester of pregnancy, most of which are short lived and not a cause for concern. Diarrhea coupled with nausea or vomiting will require preventative measures to avoid dehydration. Diarrhea accompanied by fever and pain, or that has mucus or blood in it, can be a sign of something more serious that requires a doctor’s attention.


Diarrhea, along with bloating and constipation, is usually attributable to hormones. During the first trimester, the Utah Department of Health website states, the body produces large volumes of pregnancy hormones that work to relax and slow down the gastrointestinal tract. This enables the fetus to better absorb the nutrients it needs to grow. While great for the baby, an additional end result is often embarrassing gastric annoyances that can be uncomfortable at times.

Dietary Changes


Causes of Diarrhea During Pregnancy

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Many women aim to improve their eating habits shortly after learning they are pregnant. This can include many fiber-rich foods like extra fruits and vegetables, along with extra water. While great for the baby and your health, a perhaps unintended consequence can be first trimester diarrhea according to A diet of fruits, vegetables and more water is also ideal for constipated pregnant women, which means that non-constipated women may have a reverse reaction.

Diarrhea can also be cause by lactose intolerance, which often becomes a factor when women increase milk consumption as part of a healthy diet during pregnancy. The Dr. Spock website recommends eliminating milk for a few days to see if there is any symptom relief. While doing this, it is important to obtain calcium from other sources.

Prenatal Vitamins

While the iron in some prenatal vitamins can cause constipation for some, points out that other ingredients can lead to loose stools. Similar to milk intolerance, try skipping your vitamin for a few days to see if diarrhea goes away.



Nausea After Eating in Early Pregnancy

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Pregnant women are also more susceptible to stomach viruses during pregnancy, according to the Women’s Healthcare Topics website. Diarrhea is a common symptom associated with stomach bugs of this nature.