Skip to content

Health & Pregnancy

Select An Article

Second Trimester Tests During Pregnancy

(continued)
Font Size

    continued...

    Amniocentesis: This optional test is usually performed between 15 and 18 weeks of pregnancy (but can be done earlier) for women who are 35 or older, have a higher-than-usual risk of genetic disorders, or whose MSAFP or multiple marker test results were suspicious. The procedure is done by inserting a needle through the abdomen into the amniotic sac and withdrawing fluid that contains fetal cells. Analysis can detect neural tube defects and genetic disorders. The miscarriage rate after amniocentesis varies depending on the experience of the doctor performing the procedure, averaging about 0.2% to 0.5% at 15 weeks, but the test can detect 99% of neural tube defects and almost 100% of certain genetic abnormalities.

    Cordocentesis: This test, also known as fetal blood sampling (FBS) or percutaneous umbilical cord sampling, collects fetal blood directly from the umbilical cord or fetus. This test can be used to measure anemia and blood oxygen levels and to screen for maternal Rh antibodies. Cordocentesis can be done as early as the 17th week of pregnancy.

    Fetal Doppler ultrasound: A Doppler ultrasound test uses sound waves to evaluate blood as it flows through a blood vessel. Fetal Doppler ultrasound can determine if blood flow to the placenta and fetus is normal.

    Fetoscopy: Fetoscopy allows a doctor to see the fetus through a thin, flexible instrument called a fetoscope. Fetoscopy can detect some diseases or defects that cannot be found by other tests, such as amniocentesis, ultrasound, or chorionic villus sampling. Because fetoscopy carries significant risks for the mother and fetus, it is an uncommon procedure that is only recommended if there is a much higher-than-normal chance that the baby will have an abnormality.

    WebMD Medical Reference

    Reviewed by Traci C. Johnson, MD, FACOG on September 12, 2014
    1|2
    Next Article:

    Pregnancy Week-By-Week Newsletter

    Delivered right to your inbox, get pictures and facts on
    what to expect each week of your pregnancy.

    Today on WebMD

    hand circling date on calendar
    Track your most fertile days.
    woman looking at ultrasound
    Week-by-week pregnancy guide.
     
    Pretty pregnant woman timing contaction pains
    The signs to watch out for.
    pregnant woman in hospital
    Are there ways to do it naturally?
     
    slideshow fetal development
    Slideshow
    pregnancy first trimester warning signs
    Article
     
    What Causes Bipolar
    Video
    Woman trying on dress in store
    Slideshow
     
    pregnant woman
    Article
    Close up on eyes of baby breastfeeding
    Video
     
    healthtool pregnancy calendar
    Tool
    eddleman prepare your body pregnancy
    Video