Babies can sometimes have blood in their stool that is caused by food allergies, a small anal tear or fissure, or even a temporary case of lactose intolerance. It might even be a drop of blood that came from a cracked nipple, which the baby then passed through his system. Many times the cause of blood in a baby's stool is unknown or undiagnosed. Most of the time the problem will go away on its own, but you should always check with your pediatrician when you find blood in the stool.
Blood Color Can Identify the Source
Moms usually pick up on the problem when they notice blood in the baby's diaper. The color of the blood can tell you a lot about where it originated. If it's red, it means the blood either originated externally or just inside the rectum or colon. This is often caused by a small anal fissure or tear. Sometimes a baby will have to strain to get out a stool, and this can cause a fissure.The blood is normally on the outside of the stool in this instance.
If the blood is a dark brown or black color, it usually means that it originated further up inside the gastrointestinal tract. In this case, the stool will have blood throughout it.
If your baby does have a slight external anal fissure, the most common treatment is to put a small amount of antibacterial ointment on it. It will usually heal on its own in a few days.
When to Go to the Doctor
You should always check with your baby's doctor if you notice darker blood in the stool, because it could indicate a more serious problem. If it's just a drop of blood in the diaper, or if it appears to be from an anal fissure, it might not warrant a trip to the doctor. If it is more than a drop of blood, watch your baby's behavior for additional signs and symptoms.
If your baby is happy and playful and acting like his normal little self, the blood in the stool is probably not a big problem. However, if the baby is feverish or vomiting, or if there is a significant amount of blood in the stool, call your doctor immediately.