Tests During Pregnancy Objective 3.03

Ultrasound WHAT: a test that makes sound waves to create video and still images of the fetus inside the uterus WHY: to detect abnormalities during pregnancy 1st trimester: detect heartbeat, confirm pregnancy 2nd trimester: look for abnormalities (Down syndrome) and congenital conditions 3rd trimester: observe, identify placental location WHEN: throughout pregnancy (different for everyone) HOW: the traditional procedure involves placing gel on the abdomen to work as a conductor for the sound waves. A transducer is used to produce sound waves into the uterus. The sound waves bounce off bones and tissue, returning black and white images of the fetus.

Alpha-fetoprotein WHAT: a blood test that measures the level of alpha-fetoprotein in the mother’s blood during pregnancy (results within 1 to 2 weeks) WHY: to detect possible birth defects High levels – possible neural tube defect (spina bifida), inaccurate dating of pregnancy Low levels – possible chromosomal abnormalities (Down syndrome) WHEN: between 14th and 22nd week of pregnancy WHO: Women who have a family history of birth defects Women who are 35 years or older Women who used possible harmful medications or drugs during pregnancy Women who have diabetes

Amniocentesis WHAT: a prenatal test that involves removing a small amount of amniotic fluid with a needle WHY: to check for birth defects, genetic conditions Mostly Down syndrome, cystic fibrosis, spina bifida WHEN: usually between 14-20 weeks HOW: an ultrasound is used to guide the needle into the uterus to collect the amniotic fluid. The procedure takes about 45 minutes. Risks – possible chance of miscarriage (about 1 in 400)

Chorionic Villus Sampling (CVS) WHAT: a prenatal test that involves taking a sample of the hair-like tissue in the placenta WHY: to check for certain birth defects (larger samples and faster results than amniocentesis) WHEN: 10-13 weeks HOW: Transcervical: An ultrasound guides a thin catheter through the cervix to the placenta. The chorionic villi cells are gently suctioned into the catheter. This is the most common method. Transabdominal: An ultrasound guides a long thin needle through the abdomen to the placenta. The needle draws a sample of tissue and then is removed. This procedure is similar to the amniocentesis test.

Genetic Counseling WHAT: parents who are at risk of an inherited disorder receive counseling on consequences and nature of the disorder, probability of transmitting it to the fetus, and the options for managing and planning in order to prevent, avoid, or reduce the likelihood of passing on the disorder WHO: Women who have abnormal results from routine prenatal testing. Women who received amniocentesis results that identified a chromosomal defect. Women who have an inherited disease present in a close family member (also if the father has the same issue). If there is already a child in the family with a birth defect or genetic disorder. Mothers over 35 years old. Examples: Sickle cell anemia, Tay-Sachs disease, cystic fibrosis (can you remember which ethnicities these run in frequently?)