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Pregnancy: Changes in Bowel Habits

Overview

Constipation and hemorrhoids are common problems during pregnancy.

Constipation

Constipation causes less frequent and more strained bowel movements. The bowels commonly move more slowly when you're pregnant. And iron in prenatal vitamins also can cause constipation during pregnancy.

Hemorrhoids

Hemorrhoids are swollen veins at the end of the large intestine (anus). They are often external. This means they stick out of the anus. They can also be internal. This means they are inside the lower intestine.

Hemorrhoids are common during pregnancy, because:

  • The enlarged uterus puts pressure on a large vein called the inferior vena cava. This vein drains the veins of the large intestine.
  • Constipation causes fewer and more strained bowel movements.

Pain, itching, and bright red blood on your stool are common symptoms of hemorrhoids.

Blood in the stool

Blood in the stool can come from anywhere in the digestive tract, such as the stomach or intestines. Depending on where the blood is coming from and how fast it is moving, it may be bright red, reddish brown, or black like tar.

A little bit of bright red blood on the stool or on the toilet paper is often caused by mild irritation of the rectum. This can happen if you have to strain hard to pass a stool or if you have a hemorrhoid.

If there is a lot of blood in the stool, not just on the surface, call your doctor or midwife right away. If there are just a few drops on the stool, let your doctor or midwife know today to discuss your symptoms. Black stools may mean you have blood in the digestive tract. You may need treatment right away, or the blood may go away on its own.

Certain medicines and foods can affect the colour of stool. Diarrhea medicines (such as Pepto-Bismol) and iron tablets can make the stool black. Eating lots of beets may turn the stool red. Eating foods with black or dark blue food colouring can turn the stool black.

Credits

Current as of: July 10, 2023

Author: Healthwise Staff
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