Prenatal Testing

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. http://www.mayoclinic.org/healthy-living/pregnancy-week-by-week/in-depth/prenatal-testing/art-20045177?pg=1

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 http://www.mayoclinic.org/healthy-living/pregnancy-week-by-week/in-depth/prenatal-testing/art-20045177?pg=1

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. http://www.webmd.com/baby/guide/prenatal-tests

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. http://www.webmd.com/baby/guide/prenatal-tests

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 http://www.webmd.com/baby/guide/prenatal-tests

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)

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 http://www.webmd.com/baby/guide/prenatal-tests

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 http://www.webmd.com/baby/guide/prenatal-tests

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 http://www.webmd.com/baby/guide/prenatal-tests

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? http://www.mayoclinic.org/healthy-living/pregnancy-week-by-week/in-depth/prenatal-testing/art-20045177?pg=1

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. http://www.mayoclinic.org/healthy-living/pregnancy-week-by-week/in-depth/prenatal-testing/art-20045177?pg=1

Prenatal Testing Resources

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

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) http://labtestsonline.org/understanding/wellness/pregnancy

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 http://labtestsonline.org/understanding/wellness/pregnancy

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) http://labtestsonline.org/understanding/wellness/pregnancy

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 http://labtestsonline.org/understanding/wellness/pregnancy