Maternal-Fetal Tests & Procedures
Depending on the health of the mother or baby, the mother's age, or the results of routine screening tests, our maternal-fetal specialists may perform one or more of the following tests:
- Chorionic villi sampling (CVS). This test is done very early in pregnancy, at about 10 to 12 weeks gestation. It can be used to find genetic disorders and chromosomal birth defects but cannot diagnose neural tube defects. A sample of the chorionic villus cells is collected for biopsy by inserting a catheter through the vagina and into the cervix. CVS may be offered if the mother is over 35 years old or when the parents' family history indicates an increased risk of chromosomal or genetic birth defect.
- Amniocentesis. This procedure can be done at 15 to 18 weeks or later in pregnancy. It is used to diagnose chromosomal abnormality, open neural tube defects and other defects . A small sample of amniotic fluid is used to provide genetic and health information about the fetus. This fluid is extracted through a needle inserted through the woman's abdomen and into the amniotic sac. The sample contains cells from the fetus that are then cultured and analyzed. An amniocentesis is generally offered to women who are at increased risk for chromosome abnormalities. These include women who are over age 35 at delivery, or those who have had an abnormal maternal serum screening test.
- Level III Ultrasound. This high level, comprehensive test uses sound waves to create highly detailed images of the developing fetus. Level III ultrasound may be done in response to an abnormal screening test result or if there is another reason to suspect there may be something wrong with the mother or baby. The maternal-fetal specialist can use this exam to assess development, identify organs and check for problems throughout the pregnancy. Frequency of ultrasound exams depends on the needs of each patient.
- Umbilical Doppler Vascular. This test measures the flow of blood through the umbilical cord as a way of assessing how well the placenta is functioning. An abnormal Doppler test may be a marker of fetal growth problems.
The maternal fetal specialists may also coordinate one or more of the following tests with the woman's obstetrician or other specialists:
- Genetic Counseling. Genetic counseling can help individuals and families understand their risks for having children with certain conditions, based on ethnicity, family history or maternal age. Counseling helps couples make informed decisions regarding their pregnancy by educating them about current research, testing procedures and prenatal testing options. Learn more >>
- Nonstress Test (NST). This safe, painless test monitors the movements of the fetus and changes in the fetal heart rate in response to its own movements. This test is commonly performed in the last trimester of pregnancy or after a woman passes her due date. It may be used at other times during pregnancy, too. Contractions are recorded on a paper strip along with the baby's heart rate. The test normally takes 40-60 minutes.
- Fetal Echocardiogram. Performed by a pediatric cardiologist, this ultrasound test is used to evaluate the heart of the unborn baby. Fetal echocardiography can help detect fetal heart abnormalities before birth, allowing for faster medical or surgical intervention once the baby is born. This improves the chance of survival after delivery for babies with serious heart defects.
- Biophysical Profile (BPP). This test combines a nonstress test with ultrasound. The nonstress test measures the fetal heart rate as the fetus moves. The ultrasound measures fetal breathing, movements and muscle tone, as well as amniotic fluid. Biophysical profile testing is usually performed in the last trimester of pregnancy.
- Trisomy Screening. This blood test screens for Down syndrome, Trisomy 18 and neural tube defects. It has been shown to detect approximately 90 percent of Down’s cases. Trisomy screening can be done through a second trimester blood test or as a combination of ultrasound and first trimester blood testing .