Q. My baby has had a little blood in her stool lately. Is this serious?
A. No. This is common and harmless -- and almost always due to a tiny tear in the rectum (called a rectal fissure), typically caused by constipation.
Nonetheless, you'll want to take some steps to help soften her stools, since rectal fissures can cause some discomfort and a very fussy baby.
Constipation -- and rectal tearing -- almost always occur in formula-fed babies and those who are starting to eat solid foods. So if your baby's on formula, consult her pediatrician about changing to another type that may be more intestine-friendly or ask if, in addition to the formula, you can give her a couple of ounces of plain water. For babies over 6 months, add high-fiber fruits that contain a lot of water -- like prunes and plums -- to her diet. (Four ounces of prune juice diluted with four ounces of water is a good option as well.) Talk with your baby's doctor about cutting back a bit on cereal -- this may ease her constipation too.
Meanwhile, to help her pass her stools painlessly, try smearing a bit of petroleum jelly on the outside of the anus once or twice a day. Within five to ten days, the tear should be healed.
If, however, your baby sometimes goes through phases where she has infrequent bowel movements, it's not always a sign of constipation. Stool patterns can change regularly without it signaling a problem. Babies can go a few days without having a poopy diaper -- and those who are breastfed may go less frequently than formula-fed infants, since mother's milk is digested more fully and therefore produces little waste.
When to see your pediatrician: if the pattern persists for many months or if your baby's stools are really hard (a sign that she's not getting enough water). He may prescribe a suppository or suggest additional testing.