Pregnancy Screenings, Tests, and Vaccines: A Neutral Guide for Families

Pregnancy
Written By Jessica Burrus

Last updated March 2026.

First Trimester: Common Early Tests >

Non-Invasive Prenatal Testing (NIPT/cfDNA) >

Second Trimester: Early Pregnancy Tests & Decisions >

Vaccinations During Pregnancy >

Third Trimester: Late Pregnancy Tests & Decisions >

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Congratulations! Pregnancy can feel exciting and overwhelming, and each pregnancy may bring different choices for you and your family. This guide summarizes the most common screenings, tests, and vaccines offered in a healthy pregnancy so you can discuss them with your care team.

This information is educational only and is not medical advice. Always talk with your obstetrician, midwife, or other prenatal provider about what is best for you and your pregnancy.

First Trimester: Common Early Tests

Urine Tests

Many practices schedule the first prenatal visit around 8 weeks of pregnancy, sometimes as early as 6 weeks from your last menstrual period. At that first visit, and at many future visits, you will likely provide a urine sample. The urine tests screen for:

  • Urinary tract infections

  • Diabetes

  • Preeclampsia and other complications

Urine testing looks for signs of infection or other concerns and is considered low risk and noninvasive. You pee in cups. 🙂

Initial Blood Work

Early in pregnancy, most practices order blood tests that likely include:

  • Complete blood count (CBC) to look for anemia, signs of infection, or clotting issues.

  • Blood type and RH factor, since an RH-negative status may require treatment (RH immune globulin) to prevent RH antibody development.

  • Screening for certain infections and checking immunity to some illnesses, depending on your provider and local guidelines. 

Blood draws are common in early pregnancy and are safe, with the most frequent side effect being temporary discomfort or bruising at the needle site. Personally, I have to be laying down whenever I give blood. I don’t know why, that’s my body’s rule, it’s none of my business. 

Carrier Screening

Carrier screening is usually offered at least once, often in your first pregnancy. This is a blood (or sometimes saliva) test that looks to see whether you carry certain inherited genetic conditions that could be passed to your baby. 

  • If you are found to be a carrier of a condition, then the father of the baby is often offered testing as well.

  • If you keep a record of your results, you and your partner can decide whether to repeat testing is needed in later pregnancies. 

Which conditions are included in the screening might vary depending on the lab, practice, and your family history. 

First-trimester Ultrasound

An early ultrasound is often done with the first trimester. Depending on the timing and the provider, it can:

  • Confirm the pregnancy, the location, and viability.

  • Estimate or confirm the due date.

  • Check how many babies there might be in there.

  • Look at early anatomy and the pregnancy’s attachment in the uterus

Ultrasounds use sound waves (not radiation like x-rays) and are considered safe when used appropriately in pregnancy. Here is your fair warning. In an early ultrasound a transvaginal wand is often used to get better imaging since it’s so early. Be ready for that level of invasiveness.

Non-Invasive Prenatal Testing (NIPT/cfDNA)

Non-invasive prenatal testing (NIPT), also called cell-free DNA (cfDNA) testing, is a blood test that can be done from about 10 weeks of pregnancy (some labs may offer from 9-10 weeks). It analyzes tiny fragments of placental DNA in the mother’s blood. The NIPT test can:

  • Screen for certain chromosomal conditions such as Down Syndrome (trisomy 21) and others.

  • Provide information about the fetal sex (gender), if you choose to receive it.

Important items to note:

  • NIPT is a screening test, and is not a diagnostic test. Abnormal results are usually followed by confirmatory diagnostic like testing (such as chorionic villus sampling or amniocentesis).

  • Insurance coverage and out-of-pocket costs can vary greatly for this test depending on your plan, the lab and company being used, and the reason for testing. Ask questions about your options!

Your provider or a genetic counselor can help you understand what NIPT does and does not tell you, and what alternatives are available.

 
 

Second Trimester: Early Pregnancy Tests & Decisions

Second-Trimester Blood Screening (Quad Screening)

If you did not have certain first-trimester genetic screens, or based on your provider’s protocol, you may be offered a second-trimester blood screen such as the “Quad Screen.” This test is typically done between about 15 and 22 weeks. 

The quad screen can estimate the chance of:

  • Certain chromosomal conditions

  • Some types of open neural tube defects and other birth defects. 

This is also a screening test, and positive or concerning results are usually followed by more detailed imaging and/or diagnostic testing.

20-Week Anatomy Ultrasound

The detailed anatomy ultrasound is often performed around 18-22 weeks and is sometimes called the “20-week scan.” During this scan, the sonographer looks to evaluate:

  • The baby’s organs and structures (brain, heart, spine, limbs, etc.)

  • Baby’s growth

  • Placenta location and blood flow.

  • Amniotic fluid levels.

Many practices can share printed or digital images. You can ask about 3D or 4D images if your practice offers them. My first baby they just did 3D for me. My second baby I had to ask, and they did a few. My third, they didn’t do 3D at that practice, I would have had to go somewhere else to get that if I wanted. All did print images for me though. Don’t be afraid to ask, the worst anyone can say is no. 

Glucose Screening Test

Between about 24 and 28 weeks, most pregnant patients are offered a glucose screening test to check for gestational diabetes. This usually involves:

  • Drinking a measured sugary solution.

  • Having your blood drawn at an exact time frame after the solution has been consumed.

If the screening result is higher than expected, your provider may order a longer glucose tolerance test for a more precise assessment. 

Some practices now offer alternative glucose drinks that may have different ingredients, such as fewer additives, while still providing the required amount of glucose for accurate testing. Availability can vary, and your provider or lab can tell you which options are acceptable for accurate results in their setting. With my third baby an alternative option called, “The Fresh Test” was available, through my practice. A good friend did not have the same opportunity through her office, but could do it independently through LabCorp, and have the results sent to her doctor. 

I want to preface this section by saying I’m not going to touch the vaccination debate with a 10-foot pole. Many parents have questions about vaccines in pregnancy. The goal here is to share current guideline-based information so you can make informed decisions with your care team.

Why Vaccines are offered in Pregnancy

Vaccines recommended in pregnancy aim to protect both the pregnant person and the baby. Antibodies produced after vaccination can cross the placenta and provide early protection for the infant against certain infections in the first months of life.

Vaccines Commonly Recommended in Pregnancy

According to current recommendations from major organizations such as the CDC, ACOG, and ACNM:

  • Influenza (flue) vaccine

    • Recommended for pregnant people during any trimester if they will be pregnant during flu season.

  • Tdap (tetanus, diphtheria, pertussis)

    • Recommended during every pregnancy, ideally between 27 and 36 weeks, to boost pertussis (whooping cough) antibodies for a newborn.

Recommendations are always evolving, so it is important to review current guidance and your personal risk factors with your provider.

Vaccines Generally Not Given During Pregnancy

Certain live vaccines are typically avoided during pregnancy because of theoretical risks, even though documented harm is rare. These usually include:

  • HPV

  • Measles, mumps, rubella (MMR)

  • Live attenuated influenza (Nasal spray)

  • Varicella (Chicken Pox)

  • Yellow Fever, typhoid (oral), and some other live vaccines, unless the risk of disease is judged to outweigh potential risks.

Third Trimester: Late-Pregnancy Tests and Decisions

Group B Streptococcus (GBS) Screening

Group B Streptococcus (GBS) is a type of bacteria that some adults carry without symptoms. Is not a sexually transmitted infection. Because GBS can sometimes cause serious infection in newborns, routine screening late in pregnancy has become standard in many countries. 

Key Points:

  • Timing - A vaginal and rectal swab between 36 and 37 weeks of pregnancy is each pregnancy.

  • How the test is done: A swab (similar to a long cotton swab) is gently passed just inside the vagina and then just inside the rectum. This may feel briefly uncomfortable, but is very quick and painless.

  • Results -

    • If negative, no intervention or recommendations are made. 

    • If positive, antibiotics in an IV during labor are recommended to lower the risk of early-onset GBS disease in the newborn. 

GBS colonization can come and go over time, which is why testing is recommended later in pregnancy and why results from earlier weeks may not reflect your status during delivery. Antibiotics in labor can be highly effective at preventing early onset-GBS disease, but decisions about antibiotics can be discussed in detail with your provider, including benefits and potential downsides. 

Third-Trimester Ultrasound

Some people have an additional ultrasound in the third trimester. Reasons may include:

  • Monitoring fetal growth

  • Checking amniotic fluid levels

  • Confirming baby’s position (head-down, breech, etc. ) 

  • Following up on earlier findings or specific health concerns

Whether this is routine or done only for specific indications varies by practice. 

Planning For Birth and Postpartum

In the third trimester, you will likely spend time talking with your care team about our preferences for:

  • Labor and birth (pain relief options, mobility, support people, etc.)

  • Newborn care in the hospital (vitamin K, eye ointment, newborn screening tests, feeding plans)

  • Postpartum recovery and support

You can use this time to ask questions, clarify policies at your birth location, and create a written birth preferences document if that feels helpful for you and your support team.

As always, I’m here to share my experiences, facts, and resources in a non-judgmental way so you can make the most informed decisions for yourself and your family. Your choices are personal, and my goal is to simply provide support on your journey.

The information provided in this article is for informational purposes only and should not be considered as medical advice. I am not a licensed healthcare provider. Always consult with a qualified doctor or healthcare professional before making any changes to your health, diet, or wellness routine.

Jessica Burrus

MEd, mom of three

Next

The Ultimate Guide to Prenatal Vitamins: Essential Nutrients Every Expecting Mama Needs!