Bleeding in Early Pregnancy | Causes & Risk Factors


What causes bleeding during early pregnancy?

Mild cramping and light spotting are normal early in pregnancy when the fertilized egg implants itself in the uterus. But vaginal bleeding could be a sign of something more serious. Some of the most common causes are:

Threatened miscarriage (also called threatened abortion). When a threatened miscarriage occurs, there is bleeding from the uterus (also called the womb) but the pregnancy is still normal. Sometimes a blood clot forms in the uterus and increases the risk of miscarriage. However, most women who have a threatened miscarriage will deliver a healthy baby.

Ectopic pregnancy. An ectopic (say: “eck-tah-pick”) pregnancy occurs when the fetus grows outside the uterus, usually in the fallopian tubes. The fallopian tubes are tubes that carry the egg from the ovaries to the uterus. An ectopic pregnancy can also occur on one of the ovaries, on the cervix (the opening of the uterus) or in the abdomen. Signs of an ectopic pregnancy include heavy bleeding, sharp abdominal pain and cramps. Ectopic pregnancies are life-threatening.

Spontaneous abortion (also called miscarriage). A spontaneous abortion is the spontaneous loss of a fetus. Most miscarriages occur because the fetus is not developing normally. Uncontrolled diabetes, infection, thyroid disease and hormonal problems in the mother can also cause spontaneous abortion. Other signs of a miscarriage may include sharp or dull low back or abdominal pain, cramps and tissue passing through the vagina.

Other causes of early pregnancy bleeding include infections, swollen veins in your rectum or anus called hemorrhoids (say: “hem-roids”), cervical cancer and rare pregnancy-related cancers.


First Trimester Bleeding by Mark Deutchman, MD, Amy Tanner Tubay, MD and David K. Turok, MD, MPH (American Family Physician June 01, 2009,

Written by editorial staff

Reviewed/Updated: 04/14
Created: 10/09