Is Diarrhea an Early Sign of Pregnancy?

Key takeaways:

• Diarrhea is a direct result of the body secreting too much fluid into the colon. The colon is an important regulator of your state of hydration. It absorbs or accumulates water using the feces.
• Diarrhea is when you have loose or frequent stools, indicating overhydration provoked by inflammation, infection, or other physiologic processes.
• Pregnancy is one such physiological process that may impact your state of hydration, but diarrhea is not considered a sign of being pregnant.

Diarrhea is common, but it can raise concerns when it occurs in pregnancy. Is diarrhea an early sign of pregnancy or implantation? The short answer is no.

While diarrhea may or may not be serious, knowing when it could pose risks during pregnancy is important. If you are pregnant, the dehydration that diarrhea can cause can be dangerous to both mother and baby, especially in the first trimester.

Overview: diarrhea and pregnancy

Diarrhea is not an early sign of pregnancy. That said, diarrhea during pregnancy can lead to certain risks. So if you are pregnant or could be pregnant and you are experiencing diarrhea, then remember to be careful about nutrition and hydration.

Diarrhea is a leading cause of death worldwide, but in developed countries, diarrhea is usually just a temporary nuisance. In pregnancy, this “nuisance” can potentially lead to dehydration and temporary poor nutrition.

A normal state of hydration (neither dehydrated nor overhydrated) is necessary for your body to function normally. When you are pregnant, then you can become more sensitive to any chemical imbalance in your body. Water must be just right in its amounts so that the chemistry can work. Your body regulates this hydration balance through several mechanisms:

• Breathing
• Perspiration
• Urination
• Defecation (that is, how much water is in your feces when you have a bowel movement)

Dehydration and overhydration are abnormal. Diarrhea can result from overhydration, but it can also come from inflammation or infection. If the diarrhea is caused by inflammation or infection, then it can cause too much water loss, and, thus, dehydration.

Diarrhea symptoms include:

• Loose stool, frequent stool
• Cramping and pain
• Fever

Typical early signs of pregnancy

Sometimes, in early pregnancy, you may notice that your body is retaining more fluid due to an increase in estrogen. You might notice, for example, that your ankles swell or your jewelry becomes tighter. However, these changes shouldn’t lead to diarrhea. If you have diarrhea during pregnancy, it is likely because something is wrong that is unrelated to your pregnancy.

The accepted, traditional early signs of pregnancy are:

• A delay in expected menses: If you have missed your period, then that can be an early sign of pregnancy.
• Pelvic cramping, spotting, and bloating: These symptoms can all come from implantation.
• Nausea and vomiting: hCG, a pregnancy hormone produced by the placenta, can cause nausea. Also, changes in appetite can result in dehydration, which can worsen first-trimester nausea.
• Breast tenderness: In the early stages of pregnancy, mammary glands begin to develop in preparation for breastfeeding later, which can cause breast and nipple sensitivity.
• Vascular signs: You might notice your face has a flushed or pale appearance due to alterations in your sympathetic nervous system.
• Frequent urination: Either because of fluid retention (and a need to “unload”) or because your growing uterus presses on your bladder, then you may feel the need to urinate more often.
• Processes only your doctor can identify: Some things that only your doctor can notice include a softening of your cervix, a change in the shape of your uterus, or other symptoms.

Common causes of diarrhea in early pregnancy

Being pregnant does not cause diarrhea. Instead, diarrhea is usually due to inflammation, infection, a change in diet, allergies, or adverse effects from medication. So, if you have diarrhea in the early stages of your pregnancy, then it could be from some of the following causes.

Infection

Infections cause most acute cases of diarrhea. Viruses, bacteria, and protozoa are the most frequent. The bacterium Listeria is of particular concern, however, as it can be life-threatening.

Shift in the microbiome

Although antibiotics alter the bacterial environment of your gut, antibiotics can also shift with a change in diet or even a move to another area of the country or outside of the country.

Suspect food sources (fruits, vegetables, beef, and sprouts) are typically the result of improper handling or contamination. A change in your fiber consumption, or even a pH shift from certain new ingredients or spices, can cause inflammation in the digestive system. Inflammation draws excess water into the colon, which can cause diarrhea.

Medication

Besides antibiotics, other medications can also alter the speed at which food passes through the stomach and intestines. This increase in digestion speed can lead to diarrhea.

Waterborne

Sometimes, the same pathogens that cause diarrhea in your food can also be transmitted via water, such as during recreational activities in a pool or lake.

Primary GI and other diseases

Inflammatory bowel disease (characterized by fever, abdominal pain, and bloody or mucoid diarrhea), hyperthyroidism, etc., can cause you to have diarrhea.

Read our guides on different types of diarrhea and diarrhea causes for more.

When to seek medical care for diarrhea early in your pregnancy

Any woman of reproductive age not using reliable contraception may be pregnant. If you are in this demographic, then you should consider having a lower baseline for seeking medical care.

Diarrhea causes excessive loss of not only fluids but also electrolytes, such as potassium, sodium, etc. If too much of a certain electrolyte is lost, the processes of your body that depend on that electrolyte may be affected. Everything from your heart to your kidneys uses electrolytes, so pay close attention to your electrolyte and hydration intake if you have diarrhea.

You should see a doctor if:

• You feel weak, fatigued, dizzy, or nauseous
• Diarrhea lasts more than 24 hours
• There is severe bloating or pain.

You should go to the emergency room if:

• You have any signs of dehydration, such as a fast pulse (greater than 110 beats per minute), fatigue, dizziness, severe vomiting, or bloody diarrhea.

Other reasons you may be experiencing diarrhea

Many diseases and conditions can alter your intestinal function, such as thyroid disease, autoimmune disease, celiac disease, food allergies, etc. These conditions can result in overactive (hypermotility) passage of stool that interferes with the normal hydration-balancing mechanisms.

Managing diarrhea

Diarrhea is never normal, but it is usually harmless and brief. Severe diarrhea causes water loss that can affect other organs and processes, even dangerously. Diarrhea is usually from an infection but can also be due to improper food handling and changes in the diet.

Diarrhea is not an early sign of pregnancy, but if you are, or possibly could be, pregnant, you should tell your doctor about any diarrhea lasting longer than a day, as pregnancy is overly sensitive to dehydration.

General Medicine follows a strict editorial process, including using real experts to write our articles, vetted primary sources, fact-checking, a secondary medical review, and updates as necessary. This article was medically reviewed and fact checked by Dr. Poushali Bhattacharjee, MD.

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