What Blood Test Should Be Done for Pregnancy? A Complete Guide

Learn which blood tests are done in pregnancy. Prenatal screening guide: NIPT, quad screen, and more. Essential info for expecting moms.

The primary blood test recommended for pregnancy confirmation and early screening is a quantitative hCG (human chorionic gonadotropin) test, followed by a panel of prenatal screenings including noninvasive prenatal testing (NIPT) and first-trimester combined screening. Today, updated guidelines from the American College of Obstetricians and Gynecologists (ACOG) continue to emphasize early, accurate detection of chromosomal abnormalities and maternal health conditions through a combination of blood tests. These tests are typically performed in the first and second trimesters to ensure optimal outcomes for both mother and baby.

1. First-Trimester Blood Tests (Weeks 8–13)

hCG and Progesterone

Quantitative hCG measures the exact level of pregnancy hormone, often repeated 48–72 hours apart to assess viability. Progesterone levels help confirm a healthy uterine pregnancy. Today, many labs now offer same-day results for these baseline tests.

Noninvasive Prenatal Testing (NIPT)

NIPT analyzes cell-free fetal DNA in maternal blood. It screens for trisomies 21, 18, and 13, as well as sex chromosome aneuploidies. Currently, NIPT is recommended for all pregnancies regardless of maternal age, with a detection rate over 99% for Down syndrome. This test can be performed as early as 10 weeks.

First-Trimester Combined Screening

This includes a blood test for PAPP-A and free β-hCG, combined with nuchal translucency ultrasound. It provides a risk score for Down syndrome and trisomy 18. Today, integrated screening protocols often combine NIPT results with this traditional screen for even higher accuracy.

2. Second-Trimester Blood Tests (Weeks 15–20)

Quad Screen

The quad screen measures alpha-fetoprotein (AFP), hCG, estriol, and inhibin A. It screens for neural tube defects (e.g., spina bifida), Down syndrome, and Edwards syndrome. Today, many providers use the quad screen as a backup or complementary test when NIPT is unavailable.

Glucose Challenge Test (GCT)

Between 24–28 weeks, a glucose challenge test screens for gestational diabetes. The patient drinks a sugary solution; blood is drawn one hour later. If elevated, a three-hour oral glucose tolerance test follows. Today, point-of-care hemoglobin A1c is sometimes used as a rapid initial screen.

Key Blood Tests at a Glance

Test Name	Trimester	What It Screens	Timing (Standards)
Quantitative hCG	First	Pregnancy viability, ectopic risk	As early as 2–3 weeks post-conception
NIPT (cell-free DNA)	First	Trisomies, sex chromosome issues	10 weeks onward
First-trimester combined screen	First	Down syndrome, trisomy 18	11–13 weeks
Quad screen	Second	Neural tube defects, Down syndrome, trisomy 18	15–20 weeks
Glucose challenge test	Second	Gestational diabetes	24–28 weeks

What to Expect During Blood Draws

Preparation: Most prenatal blood tests require no fasting; check with your provider for glucose tolerance tests.
Volume: Typically 2–6 vials per draw, totaling less than 20 mL.
Results: hCG and glucose screens often within hours; NIPT results take 7–10 business days today due to advanced sequencing.
Accuracy: NIPT false-positive rates are below 0.1% for trisomy 21; quad screen false positives ~5%.
Follow-up: Positive screening results lead to diagnostic testing (CVS or amniocentesis) for confirmation.

Choosing the Right Test for Your Pregnancy

Maternal Age and Risk Factors

While NIPT is now standard for all, women over 35 or those with family history of genetic disorders may benefit from expanded carrier screening (e.g., cystic fibrosis, spinal muscular atrophy). Today, comprehensive carrier panels covering over 300 conditions are often bundled with early blood work.

Multiple Gestation

For twins or higher-order multiples, NIPT is still effective but may have slightly lower accuracy. Today, specialized algorithms improve fetal fraction estimation in twin pregnancies.

Frequently Asked Questions

What blood test confirms pregnancy?

A quantitative hCG blood test is the definitive confirmation, detecting even very low levels of the pregnancy hormone as early as 10 days after conception.

Do I need both NIPT and quad screen?

Not typically. Most providers will recommend either NIPT (first trimester) or quad screen (second trimester), not both. However, if NIPT is inconclusive or unavailable, a quad screen may be used as a backup.

When are pregnancy blood tests done?

Initial hCG testing can be done as soon as you suspect pregnancy. Screening tests (NIPT, quad) have specific windows: NIPT from 10 weeks, quad screen from 15 weeks. The glucose test is standard at 24–28 weeks.

Are prenatal blood tests covered by insurance?

Under the Affordable Care Act, most insurance plans cover routine prenatal blood work without copay. NIPT may require prior authorization but is widely covered for pregnancies at increased risk; Currently, many plans cover it for all.

Your Next Step

Understanding which blood test to take during pregnancy is the foundation of a healthy prenatal journey. At prenatalscreenings.com, we provide clear, evidence-based guidance and access to the most accurate blood tests for. Order your prenatal blood test panel today and take charge of your prenatal care with confidence.