1. Prenatal Testing

2. Prenatal Testing
Prenatal testing can provide valuable information about the baby's health.
Understand the risks and benefits, and how prenatal testing might effect prenatal care.

3. Types of prenatal testing
Prenatal testing includes both screening tests and diagnostic tests.
Screening tests
Prenatal screening tests can identify whether the baby is more likely to have certain conditions
Usually can't make a definitive diagnosis
Screening tests pose no risks for mother or baby
Diagnostic tests
A more invasive prenatal diagnostic test
The only way to be sure of a diagnosis
Some tests carry a slight risk of miscarriage

4. hCG Why is this test given?: A blood test Confirms pregnancy.
Detects some birth defects
A blood test
Note: Human chorionic gonadotropin (hCG) is a hormone that is produced by the placenta after a woman becomes pregnant.

5. AFP Why is this test given?: A blood test
May indicate an increased risk for fetal neural tube defects
Spina bifida
a deformity of the spinal column
Anencephaly
the absence of all or part of the brain
Down syndrome
A blood test
Note: AFP, hCG, and estriol are tested together and are referred to as a triple screen. The quad screen refers to a test that measures AFP, hCG, and estriol but adds inhibin to improve its accuracy.

6. Ultrasound Why is this test given?:
Detect abnormalities in the baby.
Can sometimes determine the baby's gender
Uses sound waves to make an image of the baby.
Accuracy:
Depends on clarity of image
Technicians ability to read image
Risk:
none

7. Explanation of Ultrasound Test 3D Ultrasound video clip
Click on image for video clip (21 seconds) Click on image for video clips(1:58 minutes)

8. Glucose screening Why is this test given: A blood test Risk:
To determine if the mother is developing gestational diabetes
Occurs in 3%-5% of pregnant women
A blood test
Risk:
None

9. Amniocentesis Why is this test given:
To detect genetic or chromosomal disorders
over age 35 or high risk
Removes a small sample of amniotic fluid for analysis
Accuracy: 98-99%
Risk:
1/200 women who have this procedure miscarry

10. CVS Why is this test given?: To detect birth defects in the baby.
Can be done earlier in pregnancy than amniocentesis
Or when amniocentesis is not possible
Such as when there is not enough amniotic fluid
Removes a small sample of the placenta
Accuracy: 98-99%
Risk:
1/100 women who have this procedure miscarry

11. Discussion: Questions to consider
What will you do with the test results?
Will the information shape your prenatal care?
How accurate are the results?
What are the risks?
What is the expense?
If the test you're considering isn't covered by your insurance plan, are you willing and able to cover the cost of the test on your own?

12. Teacher Reference: Questions to consider
What will you do with the test results? Normal results can ease your anxiety. However, if prenatal testing indicates that your baby might have a birth defect, you could be faced with wrenching decisions — such as whether to continue the pregnancy. On the other hand, you might welcome the opportunity to plan for your baby's care in advance.
Will the information shape your prenatal care? Some prenatal tests detect problems that can be treated during pregnancy. In other cases, prenatal testing alerts your health care provider to a condition that requires immediate treatment after birth.
How accurate are the results? Prenatal testing isn't perfect. The rate of false-negative and false-positive results varies from test to test.
What are the risks? Weigh the risks of specific prenatal tests — such as anxiety, pain or possible miscarriage — against the value of knowing the results.
What is the expense? Insurance coverage for prenatal testing varies. If the test you're considering isn't covered by your insurance plan, are you willing and able to cover the cost of the test on your own?
The decision is yours
Prenatal testing can provide information that influences your prenatal care. Remember, though, some screening tests introduce the need for careful personal decisions. Ultimately, the decision to pursue prenatal testing is up to you.
If you're concerned about prenatal testing, discuss the risks and benefits with your health care provider. You might also meet with a genetic counselor for a more thorough evaluation.
A genetic counselor can help you understand:
The odds of your baby developing a particular condition
How the condition would impact your baby's life, including your baby's physical and mental development and quality of life
Possible treatment options, either during pregnancy or after birth
Taking the time to evaluate your options will help you make the best decision for you and your baby.

13. Prenatal Testing Resources

14. Prenatal Testing: Genetic tests for inherited diseases
Purpose
Test name
Why performed
When performed
Who performed on/Sample
Genetic tests for inherited diseases
Genetic testing for inherited diseases
Check carrier status for certain genetic diseases to determine risk of having a baby with such a disease
Pre-conception or first trimester
Mother and father (blood sample)
Genetic testing for hemoglobin disorders
Check carrier status for certain hemoglobin disorders to determine risk of having a baby with such a disease
Pre-conception or during pregnancy
Cystic fibrosis carrier testing
Check carrier status for CF

15. Prenatal Testing: Health conditions of the mother that affect pregnancy
Testing associated with health conditions of the mother that affect pregnancy
Immunity to rubella (German measles)
Check for immunity to the virus, which can cause birth defects
Pre-conception or first trimester
Mother (blood sample)
Human immunodeficiency virus (HIV) antibody test
Check for HIV infection so steps can be taken to reduce likelihood of transmission to the baby
Pre-conception or first trimester; may be repeated in third trimester if at high risk
Gonorrhea, chlamydia, and syphilis tests
Check for STD infections, which can cause miscarriage or infect the baby during delivery
Mother (cervical cells, urine or blood sample, depending on test)
Pap smear
Detect abnormal cervical cells, inflammation, or STDs
Mother (cells from her cervicx)
Hepatitis B screening
Detect Hepatitis B infection
Pre-conception or first trimester; may be repeated in the third trimester if at high risk
Varicella zoster viral testing
Check for immunity to chicken pox, which can cause birth defects
TORCH panel
Check for infection with toxoplasmosis and other infectious diseases that can cause birth defects
Pre-conception or first trimester, if infections suspected
Bacterial vaginosis
Detect infection, which can cause pre-term labor and birth
Pre-conception or whenever symptoms experienced
Mother (vaginal secretions)
Urine culture for bacteriuria
Detect bacterial infection in the urinary tract, which can lead to kidney infection or increased risk of pre-term delivery and low birth weight
First prenatal visit or between 12 and 16 weeks of pregnancy; may be repeated in third trimester
Mother (urine sample)
Group B streptococcus
Detect infection, which can harm the baby during birth and infect the mother’s uterus, urinary tract, and any incision made during a cesarean section
Between weeks 35 and 37 of pregnancy
Mother (specimen from vaginal and rectal areas)

16. Prenatal Testing: Monitoring of Pregnancy
Pregnancy test
Confirm pregnancy
First trimester
Mother (blood sample)
Urine screen for sugar and/or protein
Check for signs of kidney or bladder infection, undiagnosed diabetes or gestational diabetes, or preeclampsia
Each prenatal visit
Mother (urine sample)
Hemoglobin test
Check for anemia
Pre-conception and/or early in the first trimester; repeated in third trimester
Antibody screen
Check for potential incompatibility in blood type between mother and fetus (such as Rh factor antibodies)
First trimester; repeated at week 28 of pregnancy
Glucose challenge test/oral glucose tolerance test
Check for gestational diabetes
Between 24 and 28 weeks of pregnancy
Platelet count
Detect a low count or other platelet problem; platelets are important for blood clotting in case of bleeding during delivery
Third trimester

17. Prenatal Testing: Detection of fetal abnormalities or risk
First trimester Down syndrome screen
Assess risk of carrying a fetus with certain chromosomal abnormalities, such as Down syndrome
Usually between 10 weeks, 4 days and 13 weeks, 6 days of pregnancy
Mother (blood sample plus ultrasound)
Triple marker or quad marker screen
Assess risk of carrying a fetus with certain chromosomal abnormalities and open neural tube defects
Between 15 and 20 weeks of pregnancy
Mother (blood sample)
Cell-free fetal DNA
Assess risk of carrying a fetus with certain chromosomal abnormalities; currently recommended for women at high risk of having babies with these disorders
During or after the 10th week of pregnancy
Chorionic villus sampling
Detect chromosomal disorders in the fetus
Between weeks 10 and 12 of pregnancy, if recommended
Mother (cells from the placenta)
Amniocentesis
Detect certain birth defects and chromosomal abnormalities
Between 15 and 20 weeks of pregnancy, if recommended
Mother (amniotic fluid)
Cordocentesis
Detect chromosome abnormalities, blood disorders, and certain infections
Between weeks 18 and 22 of pregnancy, if recommended
Mother/fetus (fetal blood sample obtained from vein in the umbilical cord)

18. Prenatal Testing: Fetal maturity/readiness for birth
Amniocentesis
Check fetal lung development
After week 32 of pregnancy if risk of pre-term delivery
Mother (amniotic fluid)
Fetal fibronectin (fFN)
Detect fFN, negative result is highly predictive that pre-term delivery will NOT occur in the next 7-14 days
Between week 26 and 34 of pregnancy, if having symptoms
Mother (cervical or vaginal fluid sample