• Routine Prenatal Testing
• Special Prenatal Testing

Special Prenatal Testing

• First Trimester Screen. Along with maternal age, maternal blood screening tests of hCG, PAPP-A (Pregnancy-associated plasma protein A) and ultrasound measurement of nuchal translucency (fluid underneath the skin behind the baby's neck) between 11-13 weeks are used to determine risks for genetic abnormalities, including Down's Syndrome and Trisomy-18. If positive, mother may consider early diagnostic chorionic villus sampling or amniocentesis.
• Chorionic villus sampling (CVS). Test can be done between 10-12 weeks of pregnancy to diagnose and rule out birth defects. A tiny tissue sample from outside the sac where the fetus develops is obtained. Recommended in women older than 35 years old at times of delivery, family history or previous pregnancy with genetic defects, and abnormal screening test. It involves slightly higher risk of miscarriage than amniocentesis.

Second Trimester

Maternal serum screening for neural tube defects and chromosomal abnormalities.

• Triple screen. Blood test at 15-20 weeks of pregnancy for hCG (produced by placenta), estriol (produced by fetus and placenta), AFP (alpha feto-protein produced by fetus) to screen for pregnancy with increased risks for neural tube defects such as Spina Bifida and chromosomes abnormalities like Trisomy-21 (Down's Syndrome) or Trisomy-18.
• Quad screen. Blood test also includes the 4th substance inhibin-A which is more accurate in detecting Down Syndrome. The risks are calculated using maternal age, weight, race, and presence of diabetes requiring insulin. Further diagnostic testing with ultrasound and amniocentesis may be indicated to diagnose birth defects.
• Amniocentesis. Test where a small sample of the amniotic fluid surrounding the fetus is obtained for analysis between 15-18 weeks (early amniocentesis between 12-14 weeks) to diagnose chromosomal or genetic birth defects. Recommended for the same indications as amniocentesis. CVS cannot diagnose neural tube defects. It carries 1/200-1/400 risk of miscarriage. Amniocentesis can also be performed later during pregnancy for lung maturity.
• Glucose Screening Test. Blood test to screen for gestational diabetes between 26-28 weeks. If screening test is positive, a second test 3-hour Glucose Tolerance Test is recommended. If two or more of the readings are abnormal, Gestational Diabetes is diagnosed. Follow up with your doctor for plan of treatment is essential to prevent complications.

Third Trimester

• Group B Strep (GBS). Test using a swab in vagina and rectum to detect the presence of GBS bacteria between 35-37 weeks. 10-40 % pregnant women are GBS carriers. Babies born to GBS mother have 1 % chance of developing meningitis, sepsis, and death. If a woman is tested positive for GBS, IV antibiotics (usually Penicillin) is administered when the water bag breaks and during labor to prevent babies from becoming ill.
• Non Stress Test (NST). Test involving baby's heart rate monitoring in response to its own movement. NST is indicated when there is decreased fetal movement, post-term pregnancy, placental problems, high risk pregnancy with diabetes, hypertension, fetal growth problems etc.
• Biophysical profile (BPP). Test using an ultrasound exam with a non stress test (NST) to evaluate baby heart rate, breathing, body movement, muscle tone, and amniotic fluid quantity.
• Contraction stress test (CST). Test involving baby's heart rate monitoring in response to uterine contraction to determine adequate oxygen delivery to the baby.