Prenatal Screening Tests

Your health-care provider draws a small amount of blood from your arm using a needle. This test screens for conditions like hepatitis B, HIV, anemia, and sexually transmitted and blood-borne infections It also checks your blood type and Rh factor to ensure your blood matches with your baby’s. Most people find the needle either painless or only mildly uncomfortable.

Your provider may ask you to provide a urine sample at each visit. They use the sample to check for signs of infection and high protein levels. Excessive protein can indicate preeclampsia, a condition that requires medical attention.

During every prenatal visit, your provider measures your blood pressure. They wrap a cuff around your arm and connect it to a machine that reads your blood pressure. This quick and painless test helps identify conditions like preeclampsia.

Your provider uses a tape to measure your belly and track your baby’s growth. This simple and painless test ensures your baby is growing at a healthy rate.

During an ultrasound, your provider moves a wand over your belly to capture images of your baby. They apply a gel to help the wand glide smoothly. This test usually occurs between weeks 18 and 20 to check your baby’s development. If you have a high-risk pregnancy, you may need more ultrasounds. The test is painless.

You drink a sugary liquid, and your provider tests your blood sugar levels through a blood test. This screening, performed between weeks 24 and 28, checks for gestational diabetes. It’s quick and painless.

Your provider uses tests to identify conditions like Down syndrome, spina bifida, and cystic fibrosis in your baby. Some screenings use blood tests. Others, like amniocentesis or chorionic villus sampling (CVS), involve collecting samples from the fluid around your baby or tissue from the placenta. Amniocentesis uses a needle to collect fluid, and CVS involves a tool that collects tissue through your vagina. These tests may cause discomfort and carry a small risk of miscarriage. Your provider will explain the risks and benefits so you can make an informed decision.

Between weeks 35 and 37 of pregnancy, your provider swabs your vagina and rectum to test for GBS bacteria. If they find GBS, they will give you antibiotics during labor to protect your baby from infections.