Like HowStuffWorks on Facebook!

Pregnant? 10 Questions for Your First Doctor's Appointment

What prenatal tests do I need, and when?

Consider part of your first prenatal visit a fact-finding mission: Not only will you want to know how often you'll be seen during your pregnancy, but you'll also want to talk to your doctor about what tests to expect during your pregnancy and when (or if) they should be performed.

Tests include screening for birth defects, such as Down syndrome, trisomy 18, neural tube defects, heart defects and abdominal wall defects. Here are some examples of the tests you may have during your pregnancy:

  • A nuchal translucency ultrasound with a blood test is a relatively new test that measures plasma protein A (PAPP-A) and hCG to screen for Down syndrome in the first trimester.
  • Amniocentesis screens for chromosomal and genetic defects and is usually performed between 15 and 20 weeks of pregnancy. It involves using a needle to remove some amniotic fluid, which is analyzed in the lab.
  • Chorionic villus sampling (CVS) screens for the same birth defects as amniocentesis but earlier in the pregnancy (between 10 and 12 weeks). CVS tests material from the uterus, which is collected by sending a tube through the vagina and cervix.
  • Quad screen is a blood test that measures hormone (hCG and estriol) and protein (AFP and Inhibin-A) levels to screen for chromosomal abnormalities. It's performed between 16 and 18 weeks.
  • Alpha-fetoprotein (AFP) screens for spina bifida, anencephaly, chromosomal and congenital problems and is usually performed between 15 and 20 weeks.

More to Explore