Screenings for Expectant Mothers

If you're pregnant, your doctor will recommend certain screenings during your pregnancy. Screenings check your health and your baby's growth and development.

UPMC offers screenings for the first, second, and third trimesters of your pregnancy. Our goal is to help you have a healthy pregnancy and delivery.

What Are Prenatal Screenings?

Prenatal screenings are tests done during pregnancy to learn about your or your baby's health.

Doctors use screenings to check your risk of health issues that may impact your baby. They also use screenings to see if your baby is more likely to have a health issue.

Screenings can't tell for sure if you or your baby have a health condition. If a screening shows that you or your baby have a higher risk of a condition, your doctor will recommend diagnostic tests. These tests diagnose health conditions.

Many prenatal screenings are lab tests. With a lab test, doctors take a small sample of your:

• Blood.
• Urine.
• Swabs from your vagina, anus, or cervix.

The doctor then sends the sample to a lab for testing. These screenings can help find issues that may increase the risk of complications during pregnancy.

Some tests don't involve sending a sample to a lab. Instead, they check your health using tools like:

• Blood pressure cuff — To check your blood pressure.
• Ultrasound machine — To take pictures of the inside of your body.

Most of the time, you'll have screening tests at your doctor's office. Your doctor may recommend diagnostic tests like amniocentesis. You might need to see another specialist for these tests. 

Who are prenatal screenings for?

Doctors recommend screening tests for all pregnant women. They help your doctor make recommendations for your pregnancy.

Screenings are a personal decision. Some people don't want to receive certain tests, such as screenings for congenital differences.

Your doctor or a genetic counselor can talk to you about your choice to have screenings. They can also explain what your results might mean for your pregnancy and delivery.

Complications of prenatal screenings

Screenings are safe and effective. They don't increase your risk of health problems. They don't increase the risk of health problems for your baby, either.

Some diagnostic tests like amniocentesis may increase the risk of miscarriage. Like screenings, diagnostic tests are optional. If a screening test shows you or your baby may have a health issue, your doctor will talk to you about your options for diagnostic tests.

Routine prenatal testing

Doctors recommend several routine prenatal screenings for all pregnant women. Depending on your age, health history, and how your pregnancy's going, your doctor might suggest extra screenings.

Your doctor will perform some screenings regularly throughout your pregnancy. Other screenings are done at specific times.

Prenatal Screenings Throughout Pregnancy

You may receive certain screenings several times during your pregnancy. These screenings will be done at most of your prenatal appointments.

Regular screenings throughout pregnancy include:

Blood pressure checks

High blood pressure during pregnancy (preeclampsia) can cause serious health problems for you and your baby. Preeclampsia can increase your risk of death during and after giving birth. Your doctor will check your blood pressure at every visit.

Urine tests

Regular urine tests check for protein and sugar in the urine. High protein levels in the urine are a sign of preeclampsia. Sugar in the urine is a sign you're at a higher risk of diabetes.

Weight checks

Your provider will check your weight at each appointment to ensure you're not gaining too much or too little. Weight changes could indicate certain pregnancy complications.

Fundal height

Your doctor will start measuring your uterus size (fundal height) when you start showing. They use a tape measure to measure from the top of the uterus to the top of the pubic bone in centimeters. This measurement aligns with the weeks of pregnancy — when you're 20 weeks pregnant, your fundal height should be between 18 and 22 centimeters.

Prenatal Screenings in the First Trimester of Pregnancy

Doctors recommend certain screenings for the first trimester of your pregnancy. Your first trimester is from the first day of your last menstrual period until you're 14 weeks and zero days pregnant. Many of these screenings will happen at your first ob-gyn appointment, around eight to ten weeks of gestation.

A Pap test (Pap smear)

With a Pap smear test, doctors gently remove cells from the end of your cervix. They check the sample for cells that look abnormal. They also check for sexually transmitted infections, such as HPV, chlamydia, and gonorrhea. These infections can cause serious health risks if you don't treat them.

First-trimester blood tests

In the first trimester, you'll do several blood tests to learn more about your and your baby's health.

These include tests for:

• Anemia — Low iron levels or red blood cell count. Anemia can make you very tired.
• Blood type — Certain combinations of blood types between the mother and baby can cause complications. Knowing your blood type is important if you need a blood transfusion during labor.
• HIV, syphilis, and hepatitis C infection — These infections can cause pregnancy complications.
• Immunity to hepatitis B and rubella (German measles) — If you're not immune, your doctor will give you vaccines against these diseases to protect your baby.
• Rh factor — If you're Rh negative and your baby is Rh positive, your body can make antibodies against the Rh factor. These antibodies can damage the baby's red blood cells. A simple shot called RhoGAM can avoid this complication.
• Noninvasive prenatal screening test (NIPT) — NIPT is a way to perform prenatal genetic testing without an invasive test. The NIPT finds and analyzes fetal DNA in the mother's blood to screen for genetic diseases. It can also tell you the baby's sex. You can do this test any time after 10 weeks gestation.
• Genetic carrier screening — If you haven't done this before pregnancy, your doctor will suggest you do it once you're pregnant. Carrier screening of yourself and your partner allows you to find out your chances of having a child with a genetic disorder. If you and your partner are carriers of a genetic disease, your doctor may want to do more extensive diagnostic tests to determine if they have it.

First trimester ultrasounds

Ultrasounds use sound waves to see the baby inside your uterus. These images help them see your baby's size, shape, and position. Ultrasound also helps doctors see if you may have any issues with your placenta, uterus, or other reproductive organs.  

• Early ultrasound — Confirms pregnancy location and determines your baby's due date.
• First-trimester screening — This test measures the fluid-filled space at the back of your baby's neck (nuchal translucency). The results are combined with those of a blood test. This screening determines your baby's risk of congenital conditions, including Down syndrome (trisomy 21) and Edward's syndrome (trisomy 18). It is performed 11 to 14 weeks into the pregnancy.

Prenatal Screenings in the Second Trimester of Pregnancy

Your second trimester is from the fourteenth to twenty-seventh week of pregnancy. The screenings doctors recommend during your second trimester usually include:

Blood tests

Thankfully, your doctor needs fewer vials of blood in your second trimester.

You may need blood tests for:

• NIPT genetic testing if you haven't had it.
• A blood test for alpha-fetoprotein (AFP) to screen for an open neural tube.

Anatomy scan ultrasound

The anatomy scan ultrasound happens at around 20 weeks. It takes a close look at your baby and your placenta.

The anatomy scan checks your baby's organs and limbs to ensure they're developing normally. It can also tell you the baby's sex.

A fetal echocardiogram

This test uses sound waves to help an expert (a pediatric cardiologist) check your baby's heart development. It isn't a routine test that all pregnant people get. You may need this if your doctor sees a heart issue on the anatomy scan.

Instead, your doctor may recommend it if:

• You have a family history of congenital heart disease.
• Screening shows an increased risk of chromosome differences.
• You have taken certain prescription drugs that increase your baby's risk of heart problems.
• Your health issues may increase your baby's risk of heart issues.

Prenatal Screenings in the Third Trimester of Pregnancy

Your third trimester is from the twenty-eighth week of pregnancy until you give birth. Doctors often recommend these screenings during your third trimester:

Gestational diabetes screening

This test involves drinking a sugary beverage and having blood drawn to check your blood sugar levels one hour later. Doctors usually recommend this test around the 28th week of pregnancy.

If you fail the glucose screening, you'll need to do a three-hour glucose challenge. This test includes four blood draws. One before drinking the drink and three after. If any two blood sugar results are abnormal, you'll be diagnosed with gestational diabetes.

Group B strep screening

Group B strep is a common type of bacteria, but it's dangerous for newborns. If you test positive for group B, your doctor will recommend you receive antibiotics when you give birth. This can reduce the risk of health issues for your baby.

To test for group B Strep, the doctor will swab your vagina and anus. The swab will be sent to the lab. This is typically done any time after 36 weeks.

Why Choose UPMC Magee For Care?

At UPMC, our goal is to help you have a healthy pregnancy.  

Routine prenatal screenings can help spot and prevent complications. Our experts can help you make informed decisions about testing, treatment, and birth plans. UPMC offers comprehensive care during every trimester of your pregnancy.

By UPMC Editorial Staff. Last reviewed on 2024-09-05.