By Joanne Stone, Keith Eddleman, Mary Duenwald

Following are some common tests that may be recommended during your pregnancy. They may not be recommended for every pregnancy, but are included in the table for the sake of those who need them.

Common Tests during Pregnancy
TEST GESTATIONAL AGE (weeks) PURPOSE OF TEST
Dating ultrasound 7–12 Confirm viability of pregnancy, establish due date, rule out multiple gestations
Harmony, MaterniT21, Panorama, or Verifi 9–20 These are newly available tests for some women that use a sample of maternal blood to screen for genetic defects in the fetus.
Nuchal translucency test (ultrasound) 11–12 Part of the first trimester screen for Down syndrome
Chorionic villus sampling(CVS) 10–12 Diagnostic test that samples the placental tissue for genetic abnormalities; recommended for some women but should be offered to all women
AFP/quad screen 15–18 A blood test to screen for defects such as spina bifida and to complete the second trimester screen for Down syndrome
Amniocentesis 16–18 Another diagnostic test that samples the amniotic fluid for genetic abnormalities; recommended for some women but again should be offered to all women
Anatomy ultrasound 18–22 An ultrasound to look at the baby from head to toe to make sure he is developing normally (to rule out many birth defects)
Glucose screen 24–28 A test for gestational diabetes
Group B strep (GBS) swab 35–37 To see if the birth canal is colonized with group B strep bacteria (if so, mom will be given antibiotics during a vaginal delivery to protect the baby)
Non-stress test (NST) 40–42 A test of the baby’s heart rate patterns to determine fetal well-being, despite going past his due date. Often done earlier in pregnancy for other complications like high blood pressure and diabetes.
Biophysical profile (BPP) 40–42 An ultrasound test to determine fetal well-being. Also often done earlier in pregnancy for other complications. Includes an assessment of amniotic fluid volume.