Amniotic fluid surrounds the baby during pregnancy. Amniocentesis is the removal of a small amount of this fluid for testing.

  • Call Your Doctor

    After arriving home, contact your doctor if you have:

    • Signs of infection, including fever and chills
    • Nausea or vomiting
    • Pain or cramping in your lower abdomen or shoulder
    • Vaginal bleeding or a loss of fluid from the vagina
    • Redness, swelling, increasing pain, excessive bleeding, or discharge from the amniocentesis site
    • New, unexplained symptoms

    In case of an emergency, call for medical help right away.

  • Definition

    Amniotic fluid surrounds the baby during pregnancy. Amniocentesis is the removal of a small amount of this fluid for testing.

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  • What to Expect

  • Reasons for Procedure

    Amniocentesis is most often done to see if there is an abnormality in your baby's genes (DNA). It can also be done to see if your baby is developing correctly. Later in pregnancy, it can be done to determine the maturity of your baby's lungs.

    Factors that indicate that you may need this procedure include:

    • Age: over 35 years at the time of delivery
    • Family history of chromosome abnormality
    • Family history of inherited disorder

    • Family history of neural tube defect—problems in spine and brain growth, such as
      spina bifida
      or anencephaly

    • Abnormal results from early screening tests for chromosomal abnormalities

    Depending on your risk factors, cells in the amniotic fluid are tested for:

    • Chromosome abnormalities. The results are usually ready within 14 days.
      Missing or extra chromosomes lead to physical birth defects and
      intellectual disability.
      Down's syndrome
      is one example.

    • Inherited genetic diseases—Test results are usually ready in 1-5 weeks. Examples include:

      • Tay-Sachs disease—Most frequent in the Ashkenazi Jewish population
      • Cystic fibrosis—Most frequent in Caucasians of northern European ancestry
      • Sickle cell disease—Most frequent in the black race

    Amniocentesis may also be done:

    • To determine whether the baby's lungs are mature
    • In high-risk pregnancies that may require early delivery
    • There is concern for Rh-sensitization pregnancy

  • Possible Complications

    Complications that may occur with an amniocentesis include:

    • Bleeding, cramping, and leaking fluid from the vagina
    • Infection
    • Mixing of blood if you and your baby have different blood types
    • Need for repeat testing
    • Harm to the fetus by the needle—Rare
    • Miscarriage—Rare

    Factors that may increase your risk of complications include:

    • Maternal
    • Previous abdominal surgery

    Be sure to discuss these risks with your doctor before the procedure.