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Amniocentesis

What is an amniocentesis?
This is a procedure that is performed on some pregnant women in the office. Dr. Hardy uses an ultrasound machine to guide him to a large pocket of fluid inside the uterus. He will use a needle to remove a small amount of amniotic fluid and send for laboratory analysis.

Why would I need an amniocentesis?
This test is very important in diagnosing abnormalities of an unborn child. The best time to perform an amnio is between the 15th and 18th weeks of pregnancy.
Amniocentesis is often done for one or more of the following reasons:

  • Maternal age is over 35 yrs at the time of delivery.
  • Patient had abnormal results from blood screening test such as Quad screen or AFP.
  • Risk of metabolic disease or neural tube defect because of previous experience or family history.
  • Either parent has a chromosome abnormality.
  • Mother has previously had a child with a chromosome abnormality, such as Down Syndrome.
  • Mother carries a sex-linked abnormality, and the sex of the unborn child must be determined.
  • To evaluate fetal lung maturity or other conditions must be determined late in pregnancy.
  • To evaluate pregnancy for infection.
  • Mother produces antibodies, most commonly to the fetal blood cells, that can cause the unborn child to be anemic. The amniotic fluid is tested for a chemical (bilirubin) that serves as a marker for fetal anemia.
  • To remove excess amniotic fluid, most commonly in twins when one baby has too much amniotic fluid and the other has too little.

What should I expect during the procedure?
You will schedule the amnio during office hours to be performed by Dr. Hardy. These are done in our Virginia Beach office using the ultrasound machine as guidance. A hollow needle is inserted through the abdominal wall into the uterus. The needle will cause temporary pain but should not hurt more than any injection. Some women report mild to moderate cramping, or a feeling of pressure, during the procedure. A small amount of fluid is removed and sent off for laboratory evaluation.

What should I expect after the procedure?
You should have someone drive you to and from the appointment. You may experience mild lower abdominal cramping. You should rest for the remainder of the day and can return to normal activity the next day. The results may take up to 2 weeks to be completed. You will have a 2 week follow up appointment with Dr. Hardy.

What are the risks of an amniocentesis?
It is rare that a miscarriage may occur after the procedure. There could be some damage to the baby such as slight dimpling of the skin where the baby was poked during the procedure and very rarely death. The rate of miscarriage or fetal death as a result of the procedure is less than 0.5 to 1%. Other risks are excessive bleeding or surgical wound infection.

What are the benefits of an amniocentesis?
There are many benefits of having an amnio. If the laboratory results show a normal chromosome analysis of the baby, there is a relief of unnecessary worry and fear for the parents-to-be. If the chromosome analysis is abnormal, the parents can begin to get their resources in order for delivery and if any procedures need to be done before delivery, there is plenty of time to take care of them. There is also time to terminate the pregnancy if the parents-to-be decide to do that.

When should I call the office?

You should call the office if you experience:

  • Significant loss of fluid from the vagina
  • Nausea and vomiting
  • Pain in the lower abdomen or shoulder
  • Bleeding from vagina or puncture site
  • Signs of infection, including headache, muscle aches, dizziness or a general ill feeling and fever