What Is Amniocentesis?
Amniocentesis, also referred to as an amniotic fluid test, is a diagnostic procedure that removes a small sample of amniotic fluid from the uterus for testing. Usually scheduled between the 15th and 18th week of pregnancy, the test can provide valuable insight into the baby's development, helping to identify any chromosomal abnormalities or genetic diseases.
An amniocentesis test is often recommended for pregnant women at an advanced maternal age or who are at an increased risk of having a baby with a birth defect or genetic disorder. To schedule a consultation with a healthcare practitioner in who specializes in prenatal testing, call (718) 743-0505 or contact us online.
What Does Amniocentesis Test For?
The amniotic fluid which surrounds the fetus is a source of valuable health information pertaining to your baby's development. Among the contents of the amniotic fluid are cells shed by the fetus that contain genetic information. These cells can help to diagnose:
- Genetic and chromosomal conditions, such as Down syndrome or sickle cell anemia
- Neural tube defects (birth defects of the brain and spine), such as spina bifida and anencephaly
If your baby has a heightened risk of having any of these conditions, your healthcare practitioner may recommend an amniocentesis at 15 to 18 weeks of pregnancy.
An amniotic fluid test may also be recommended later in pregnancy (during the third trimester) to check:
- Uterine infection
- The severity of anemia in babies who have Rh sensitization
- Fetal lung maturity, or whether or not the baby’s lungs are developing properly, in cases where early delivery may be necessary to prevent complications
- If there is too much amniotic fluid surrounding your baby (polyhydramnios) which requires removal
What to Expect During an Amniocentesis Procedure
As part of amniocentesis preparation, your healthcare provider will review your medical history, asking about your medications, allergies, and current medical conditions, such as if you have any bleeding disorders.
The entire amniocentesis test procedure takes roughly 30-45 minutes. To begin, you will lie down on an exam table. Your healthcare practitioner will clean your abdomen with an alcohol or iodine solution. An ultrasound is then used to verify the infant's heartbeat and placement in the uterus. Once your healthcare provider has found a spot that's far away from the baby, a long, thin needle is inserted into your uterus through your abdomen; this may cause a stinging or cramping sensation. A sample of amniotic fluid is removed through the hollow needle; if the mother is carrying twins, samples will be taken from each embryonic sac.
After an amniocentesis, your healthcare provider may monitor the baby with an external fetal monitor. It is important to relax for the remainder of the day. Have someone drive you home and refrain from strenuous activity, such as exercise or sexual intercourse. While minor cramping may occur over the next 24-48 hours, it is important to contact your healthcare provider if you experience significant discomfort or vaginal spotting.
Amniocentesis results can take up to one to two weeks. A positive test indicates that your baby has one of the conditions tested for during the procedure. It is important to meet with your practitioner and other specialists to learn more about the condition and to discuss your options.
There is a small risk (less than 1 percent) of miscarriage from an amniocentesis. Other rare amniocentesis complications that warrant medical attention may include:
- Premature labor
- Cramping, bleeding or leaking of amniotic fluid
Talk with your healthcare provider about whether or not amniocentesis is right for you and your baby. To make an appointment with a specialist who can perform an amniocentesis fluid test in , call (718) 743-0505 or contact us online.