Pregnancy is an exciting and transformative time, but it also comes with a series of routine tests to ensure the health of both the mother and the developing baby.
These tests help monitor your pregnancy, detect potential complications, and provide early interventions when necessary. While some tests are standard for all pregnancies, others are only performed under specific circumstances.
We’ve compiled a comprehensive guide to the routine tests performed during pregnancy, ordered by when they are typically done, along with how they are performed and why they are used.
While we’ve provided a general timeline for tests, your healthcare provider may adjust that timeline as needed, and they may even suggest additional tests for special circumstances.
Blood Tests: First Prenatal Visit
Blood tests during the first prenatal visit provide important information about the mother’s health and potential risks to the pregnancy.
Blood tests during your first visit can determine blood type and Rh factor, essential for identifying Rh incompatibility, a condition that can lead to complications if not managed properly. These tests also screen for anemia, which can affect mom’s energy levels and baby’s growth, along with immunity to infections like rubella, which can cause birth defects if contracted during pregnancy.
Additionally, blood tests check for sexually transmitted infections (STIs) such as HIV, syphilis, and hepatitis B, which can be transmitted to the baby if left untreated. Genetic conditions like sickle cell anemia or thalassemia may also be identified, allowing for early planning and care.
When: During the first prenatal visit (usually between weeks 8 and 12).
How it’s performed: A blood sample is taken from the mother’s arm.
Standard Test? Yes, this is a standard test for all pregnancies.
Special circumstances: Rh factor testing is particularly important for Rh-negative mothers, as they may require additional care to prevent complications.
Non-Invasive Prenatal Testing (NIPT): Weeks 10-12
Non-Invasive Prenatal Testing (NIPT) is an advanced screening tool that analyzes fetal DNA in the mother’s blood to assess the risk of chromosomal abnormalities such as Down syndrome, trisomy 18, and trisomy 13. This highly accurate test poses no danger to the fetus, making it a preferred option for many expectant parents.
While it is optional, it is often recommended for women over 35, those with a family history of genetic disorders, or those with abnormal ultrasound findings. NIPT provides valuable information that can help parents prepare for the baby’s needs or make informed decisions about further diagnostic testing.
When: Between weeks 10 and 12.
How it’s performed: A blood sample is taken from the mother.
Standard Test? This test is optional and often recommended for high-risk pregnancies.
Special circumstances: Typically offered to women over 35, those with a family history of genetic disorders, or abnormal ultrasound findings.
Chorionic Villus Sampling (CVS): Weeks 10-13
Chorionic Villus Sampling (CVS) is a diagnostic test that provides detailed information about the baby’s genetic makeup. It is typically offered to women at higher risk of having a baby with genetic disorders, such as cystic fibrosis, sickle cell anemia, or chromosomal abnormalities like Down syndrome.
The test involves taking a small placental tissue sample containing the same genetic material as the baby.
While CVS carries a small risk of miscarriage, it provides definitive answers early in pregnancy, allowing parents to make informed decisions about their care and prepare for the baby’s needs.
When: Between weeks 10 and 13.
How it’s performed: Using a needle, a small placental tissue sample is taken through the cervix or abdomen.
Standard Test? This test is optional and typically offered to high-risk pregnancies.
Special circumstances: Recommended for women with a family history of genetic disorders or abnormal screening results.
Ultrasound: Weeks 6-9 and Weeks 18-22
Ultrasounds are a cornerstone of prenatal care, providing a window into the baby’s development. The early ultrasound, typically performed between weeks 6 and 9, confirms the pregnancy, checks the baby’s heartbeat, and estimates the due date.
The anatomy scan is performed between weeks 18 and 22 and evaluates the baby’s growth and development, including the brain, heart, spine, and other organs. This scan can detect structural abnormalities and ensure the baby is growing as expected.
Ultrasounds also help identify multiple pregnancies and monitor the placenta and amniotic fluid levels.
When: Early ultrasound between weeks 6-9; anatomy scan between weeks 18-22.
How it’s performed: A transducer is moved over the abdomen or inserted vaginally to create images of the baby.
Standard Test? Yes, ultrasounds are standard but may vary in frequency depending on the pregnancy.
Special circumstances: Additional ultrasounds may be needed for high-risk pregnancies or if abnormalities are suspected.
Amniocentesis: Weeks 15-20
Amniocentesis is a diagnostic test that analyzes amniotic fluid to detect genetic disorders, neural tube defects, and certain infections. It is often recommended for women over 35, those with abnormal screening results, or those with a family history of genetic conditions.
The test provides definitive information about the baby’s health, helping parents make informed decisions about their pregnancy and prepare for any special care the baby may need.
While amniocentesis carries a small risk of miscarriage, it is considered a valuable tool for high-risk pregnancies.
When: Between weeks 15 and 20.
How it’s performed: A small amount of amniotic fluid is extracted using a needle inserted through the abdomen.
Standard Test? This test is optional and typically offered to high-risk pregnancies.
Special circumstances: Recommended for women over 35, those with abnormal screening results, or a family history of genetic conditions.
Glucose Screening Test: Weeks 24-28
The glucose screening test is a key part of prenatal care, designed to detect gestational diabetes, a condition that can develop during pregnancy. Gestational diabetes occurs when the body cannot produce enough insulin to handle the increased blood sugar levels during pregnancy.
If left untreated, it can lead to complications such as a larger-than-average baby, which may increase the risk of cesarean delivery or birth injuries. It can also raise the mother’s risk of developing type 2 diabetes later in life.
Early detection through this test allows for dietary changes, monitoring, or medication to manage the condition and ensure a healthy pregnancy.
When: Between weeks 24 and 28.
How it’s performed: The mother drinks a sugary solution, and blood is drawn an hour later to measure glucose levels.
Standard Test? This is a routine test for all pregnancies.
Special circumstances: A follow-up glucose tolerance test may be required if results are abnormal.
Group B Streptococcus (GBS) Test: Weeks 36-38
The Group B Streptococcus (GBS) test is a routine screening performed late in pregnancy to check for the presence of a common bacterium that can be harmful to the baby during delivery.
While GBS is generally harmless to adults, it can cause serious infections in newborns, such as pneumonia, meningitis, or sepsis.
If the test is positive, antibiotics are administered during labor to reduce the risk of transmitting the bacteria to the baby. This simple intervention can prevent potentially life-threatening complications and ensure a safer delivery.
When: Between weeks 36 and 38.
How it’s performed: A swab is taken from the vagina and rectum.
Standard Test? This is a standard test for all pregnancies.
Special circumstances: If GBS is detected, antibiotics are given during labor to prevent transmission to the baby.
Fetal Monitoring: Third Trimester
Fetal monitoring is a critical tool used during the third trimester and labor to ensure the baby tolerates pregnancy and delivery well. It involves tracking the baby’s heart rate and the mother’s contractions to detect any signs of distress.
This information helps healthcare providers make timely decisions about interventions, such as changing the mother’s position, administering oxygen, or proceeding with a cesarean delivery if necessary.
Fetal monitoring is especially important in high-risk pregnancies or when complications arise, as it provides real-time information about the baby’s well-being.
Check out our article about fetal heart monitoring and fetal heart tracing and why they are both important.
When: Typically in the third trimester or during labor.
How it’s performed: A belt with sensors is placed on the mother’s abdomen to monitor the baby’s heart rate and contractions.
Standard Test? Yes, this is standard during labor and may be used earlier in high-risk pregnancies.
Special circumstances: Used more frequently in high-risk pregnancies or if complications arise.
Urine Tests: Throughout Pregnancy
Urine tests are a simple yet vital part of prenatal care and are regularly performed to monitor the mother’s health. They screen for urinary tract infections (UTIs), which, if untreated, can lead to more serious complications like kidney infections or preterm labor.
Protein levels in the urine are checked to detect preeclampsia, a condition characterized by high blood pressure and potential organ damage. Elevated glucose levels may indicate gestational diabetes, which can affect the baby’s growth and increase the risk of complications during delivery.
Regular urine tests ensure that any issues are caught early and managed effectively.
When: Routinely at prenatal visits.
How it’s performed: A sterile cup collects a urine sample.
Standard Test: Yes, this is a routine part of prenatal care.
Special circumstances: Additional testing may be required if protein or glucose levels are abnormal.
Routine tests during pregnancy are essential for monitoring the health of both the mother and the baby. While some tests are standard for all pregnancies, others are optional or performed under specific circumstances.
By understanding the purpose and timing of these tests, expectant parents can feel more informed and prepared throughout their pregnancy journey.
As always, you should consult directly with your healthcare provider before deciding which tests will be performed during your labor. Use the information above to make informed decisions, but always work with your doctor to ensure you and your future baby receive the proper care.