A threatened abortion, sometimes called a threatened miscarriage, is a condition in which vaginal bleeding or abdominal cramps suggest that a woman’s body may terminate a pregnancy. The term refers to the possibility of a natural miscarriage and not to a deliberate termination of the pregnancy. A threatened abortion occurs during the first trimester of pregnancy. Treatment involves steps to try to help the woman’s body continue the pregnancy.

Symptoms of a threatened abortion are vaginal bleeding, which may be heavy or light and may or may not be accompanied by abdominal cramping. Abdominal crapping without vaginal bleeding can also be a symptom. Vaginal bleeding during early pregnancy can have many causes, some of which are not necessarily reason for concern. Other possible causes of vaginal bleeding during early pregnancy are the implantation of the embryo, an infection, or an ectopic pregnancy, which is one in which the fetus is developing outside of the womb. Additional symptoms of a miscarriage include lower back pain, abdominal pain, and the passing of clots in vaginal bleeding.

About 20 to 30 percent of pregnancies include symptoms of a threatened abortion, with about 10 to 15 percent of pregnancies ending in miscarriage. About half of pregnancies in which there are symptoms of threatened abortion end in miscarriage. Risk factors include infection, trauma, and the age of the mother. Women who are older at the time of pregnancy are more likely to experience the symptoms of a threatened abortion and to miscarry.

In a threatened abortion, treatment most often involves bed rest and not engaging in sexual intercourse until the symptoms have resolved. Progesterone, which is a hormone that helps maintain a pregnancy, may also be given. In some cases, the mother’s body may produce antibodies that react against the fetus’ blood type. If testing reveals this to be an issue, the mother may be given an injection of Rho(D) immune globulin to stop the production of the antibodies.

When an expectant mother visits her doctor and has symptoms of a threatened abortion, the physician will likely conduct tests to determine if the pregnancy is still viable and to determine if there are any health issues. A pregnancy test may be done. The doctor may do a complete blood count to determine how much blood the mother has lost, a progesterone level test, and a white blood count to determine if there is an infection present.