Why Pregnancy Blood Work Matters
When you’re expecting, routine checkups become an essential part of your health, and one of the most important tools your care team uses is pregnancy blood work. These tests are designed to monitor your well-being and your baby’s development, catch any concerns early, and personalize your care plan.
Blood testing is done at different points throughout pregnancy, depending on your medical history, trimester, and overall risk factors. While the number of blood tests can feel overwhelming at times, they are generally quick, safe, and incredibly informative. Understanding what’s being tested and why can help you feel more confident and empowered at every stage.
First Trimester Blood Work: What to Expect Early On
Your first round of blood work typically happens during your initial prenatal appointment, often between 8 and 10 weeks of pregnancy. These baseline labs give your provider a broad look at your health and help confirm that your pregnancy is progressing normally.
Here are some common tests you can expect:
- Human Chorionic Gonadotropin (hCG) blood test – Confirms pregnancy and tracks early development
- Blood type and Rh factor – Determine compatibility between your blood and your baby’s
- Complete Blood Count (CBC) – Screens for anemia, infection, and clotting issues
- Infectious disease testing – Tests for HIV, hepatitis B/C, and syphilis
- Prenatal panel – A collection of tests often ordered together in early pregnancy
- Thyroid and Rubella immunity testing, if indicated
You may also hear your provider mention quantitative hCG or beta hCG levels, which are used to assess how your pregnancy is progressing in its earliest weeks. Even if you don’t have symptoms, this testing helps detect conditions that could impact your care.
Genetic and Carrier Testing Options
Some genetic screening options may be offered in the first or early second trimester. These tests look for inherited conditions or chromosomal differences. They can include:
- Carrier screening – Checks if you or your partner carries gene mutations for inherited disorders like cystic fibrosis
- Noninvasive Prenatal Testing (NIPT) – A blood test that uses blood samples to assess the risk of chromosomal conditions like Down syndrome
- Screens for trisomy 13, 18, and 21, depending on what’s offered by your clinic
These are screening tests, not diagnostic tests. If results suggest a higher risk for certain conditions, they may be followed by an ultrasound or procedures like amniocentesis.
It’s always a good idea to talk with your doctor or provider about whether these tests make sense for you, especially if you have a family history of genetic conditions or are 35 or older.
Second and Third Trimester Tests
As your pregnancy progresses, bloodwork continues to play an important role. In the second trimester, your provider may recommend:
- Glucose challenge test – Screens for gestational diabetes, usually around 24–28 weeks
- Hemoglobin and iron levels – Checks for anemia, a common condition in pregnant women
- Antibody screen – Repeated if you are Rh-negative
- Infectious disease screening – Retesting for certain STIs or immunity
- Fetal health monitoring – In combination with labs, to track growth and development
This is also the window when you may be eligible for the PreTRM® Test—a simple blood test that can predict the risk of spontaneous preterm birth. It’s typically offered between 18–20 weeks and is the only clinically validated test of its kind. Ask your provider whether it’s appropriate for your care plan.
While many of these tests are routine, your provider may adjust them based on your health history, symptoms, or any emerging concerns.
Interpreting Results: When to Expect Them and What They Mean
Waiting for lab results can feel nerve-wracking. Here’s what to expect once your blood work is completed:
- Turnaround time: Some tests (like Complete Blood Count, or CBC) come back within a day or two, while others (like genetic screens) may take a week or more
- Communication: Your clinic may call, email, or upload results to your patient portal
- Follow-up: If any results are abnormal, your provider will explain the next steps. It might be a repeat test, a referral, or simply a wait-and-see approach
It’s important to remember: an “abnormal” result doesn’t always mean something is wrong. It’s just a signal for more information.
Questions to Ask Your Doctor About Blood Work
Understanding your pregnancy blood work starts with asking the right questions. Here are a few you can bring to your next appointment:
- What blood tests are being done today, and why?
- Will any of these tests impact my care or delivery plan?
- How will I get my results, and how long will it take?
- Are there any tests you recommend based on my personal or family history?
- Can we review my last round of lab results together?
Your provider wants you to feel informed and involved. Don’t hesitate to speak up if anything is unclear or you’re feeling anxious about a test or result.
What to Remember About Pregnancy Blood Work
Pregnancy blood work is one of the most effective ways to stay proactive and informed about your health and your baby’s development. These tests help your care team detect concerns early, customize your prenatal care, and support the healthiest outcome possible for you and your baby.
You don’t need to know every detail, but understanding the basics can help reduce stress, spark helpful conversations, and give you confidence as you move through each trimester.
Want to understand the full schedule of prenatal care? Read our guide to prenatal visits and what to expect each trimester.
Pregnancy Blood Work FAQs
What blood tests are done during pregnancy?
Common blood tests include CBC, blood type, and Rh factor, thyroid levels, and screenings for infections and genetic conditions.
What do they check in a blood test for pregnancy?
Blood work looks for key markers of your health and your baby’s development, including hormone levels, immunity, and risk factors for complications.
How many times do you get bloodwork while pregnant?
Most pregnant people have blood work in the first, second, and sometimes third trimesters, depending on personal risk and provider recommendations.
What type of blood test is required for pregnancy?
An early hCG blood test confirms pregnancy, followed by routine labs like the prenatal panel.
What blood tests are repeated during pregnancy?
Rh antibody screens, iron levels, and infection screenings may be repeated later in pregnancy to monitor ongoing health.