As you enter the final stage of pregnancy, the third trimester brings excitement and anticipation. Still, it’s also a critical time for monitoring your health and your baby’s well-being. At Capital Women’s Care Rockville, Dr. Judith Gurdian emphasizes the importance of third-trimester screening tests to ensure that both mother and baby are healthy and prepared for safe delivery. These tests help detect potential complications and ensure any issues can be addressed promptly.
In this blog, we will explore the essential screening tests typically conducted in the third trimester, their importance, and what you can expect during this phase of pregnancy.
Why Are Third Trimester Screening Tests Important?
The third trimester, which spans weeks 28 to 40, is crucial for your baby’s development and health. Routine tests during this stage help your healthcare provider monitor the growth and position of your baby, ensure your body is ready for labor, and identify any conditions that might require special care or treatment.
Regular checkups and screenings are essential for the early detection of potential complications such as gestational diabetes, preeclampsia, or infections. Dr. Gurdian stresses that timely intervention based on these tests can make a significant difference in ensuring a smooth delivery and a healthy baby.
Glucose Tolerance Test (GTT)
One of the most important screening tests in the third trimester is the glucose tolerance test (GTT), which screens for gestational diabetes. Gestational diabetes can develop in pregnant women who did not have diabetes before pregnancy. If left untreated, it can lead to complications such as excessive birth weight, preterm birth, and an increased likelihood of a cesarean section.
During the GTT, you will be asked to drink a glucose-rich solution, and your blood sugar levels will be tested after a certain period. If your glucose levels are elevated, you may need further testing or management to keep your blood sugar under control for the remainder of your pregnancy.
Group B Streptococcus (GBS) Screening
Group B Streptococcus (GBS) is a type of bacteria found in pregnant women’s digestive system or birth canal. Although it’s harmless to most adults, it can cause serious infections in newborns if passed on during delivery. Dr. Gurdian advises that all women should be tested for GBS between weeks 35 and 37 of pregnancy.
GBS screening involves a simple swab of the vagina and rectum. If you test positive, antibiotics will be administered during labor to reduce the risk of passing the infection to your baby.
Ultrasound for Fetal Growth and Position
In the third trimester, an ultrasound may assess your baby’s growth, amniotic fluid levels, and uterine position. Dr. Gurdian highlights the importance of this test for determining whether the baby is in a head-down position, which is ideal for a vaginal delivery. If your baby is breech (feet or buttocks first), your healthcare provider will discuss options for attempting to turn the baby or plan for a cesarean section if necessary.
Additionally, ultrasounds can identify any growth restrictions or other conditions that might affect your baby’s health, allowing for timely medical intervention.
Non-Stress Test (NST)
If your healthcare provider has concerns about your baby’s health or if you have a high-risk pregnancy, you may be scheduled for a non-stress test (NST). This test monitors your baby’s heart rate in response to its movements, which helps assess how well your baby is doing inside the womb. Dr. Gurdian points out that the NST is non-invasive and can provide valuable information about your baby’s oxygen supply and overall health.
During the test, a belt with a sensor is placed around your abdomen to monitor your baby’s heartbeat. The test typically lasts 20 to 40 minutes, and the results can help determine whether your baby is in any distress.
Biophysical Profile (BPP)
A biophysical profile (BPP) is a more detailed test that combines an ultrasound with a non-stress test. This screening evaluates your baby’s heart rate, breathing, movements, muscle tone, and amniotic fluid levels. It’s often recommended for women with high-risk pregnancies or if there are concerns about the baby’s health based on previous tests.
Dr. Gurdian emphasizes that the BPP provides a comprehensive assessment of your baby’s well-being and helps determine if any immediate medical intervention is necessary to ensure safe delivery.
Amniotic Fluid Volume (AFI) Assessment
The amount of amniotic fluid surrounding your baby is an important factor in your baby’s health. Low amniotic fluid levels (oligohydramnios) can indicate issues with the placenta or fetal kidneys. In contrast, excessive fluid (polyhydramnios) can be associated with complications such as gestational diabetes or fetal abnormalities.
Amniotic fluid volume is typically measured during an ultrasound. If the levels are abnormal, Dr. Gurdian may recommend further testing or monitoring to ensure your baby remains healthy throughout the third trimester.
Doppler Ultrasound
A Doppler ultrasound is a specialized test that measures the blood flow in the umbilical cord, placenta, and baby’s brain. This test is often performed if there are concerns about your baby’s growth or if you have conditions such as preeclampsia or hypertension.
By evaluating blood flow, healthcare providers can determine if your baby is receiving enough oxygen and nutrients. Dr. Gurdian notes that this test can guide decisions about whether an early delivery is necessary.
Screening for Preeclampsia
Preeclampsia is a condition characterized by high blood pressure and protein in the urine, and it can develop in the third trimester. It poses risks to both mother and baby, including preterm delivery and complications during labor. Routine blood pressure checks and urine tests are essential for detecting signs of preeclampsia early.
If preeclampsia is suspected, Dr. Gurdian may order additional blood tests or recommend close monitoring to manage the condition and reduce risks for you and your baby.
The Final Weeks: What to Expect
As you approach your due date, frequent checkups become even more important. Dr. Gurdian advises that regular screenings, ultrasounds, and non-stress tests are all part of monitoring your baby’s readiness for birth and ensuring that you’re in optimal health for labor. In these final weeks, it’s also important to discuss your birth plan with your healthcare provider and be prepared for any last-minute changes that may arise based on your screening results.
Preparing for a Healthy Delivery
Third-trimester screening tests are essential for safeguarding your health and your baby’s. You and your healthcare provider can make informed decisions about your delivery by undergoing these tests, ensuring you’re prepared for any potential complications. Dr. Judith Gurdian and the Capital Women’s Care Rockville team are committed to providing comprehensive prenatal care and guiding you through the final stages of pregnancy with confidence.
You’re taking important steps toward a healthy and safe delivery by staying informed and proactive about your screenings.
Sources:
Johnson, M. (2019). Importance of Prenatal Screening in the Third Trimester. Maternal and Fetal Medicine Journal.
Taylor, A., & Collins, R. (2021). Ultrasound Monitoring in Late Pregnancy. Journal of Obstetrics and Gynecology.
Parker, S. (2020). Gestational Diabetes: Risks and Management Strategies. Clinical Pregnancy Review.
