Before you will be a supermom, you will be super pregnant. That period is the third trimester of pregnancy. Congratulations! You have made it to the last three months of your gestation. You can say goodbye to seeing your toes now, until your due date. The last trimester is not only about waiting for childbirth. It is also about the rapid growth of your baby. The fleeting growth of 20 to 38 weeks should be monitored with the help of 3D/4D/HD Ultrasound scans and tests.

This week on LadiesAndBabies, we will explain the various tests during pregnancy third trimester.

Main Third Trimester Scans And Tests

As your delivery date draws closer, you may need to make more visits to the gynaecologist. A diverse range of tests during pregnancy third trimester is conducted based on the mother’s overall health. Expecting moms with high-risk pregnancy may have to undergo more inspections than others.

Group B Strep Test

Group B streptococcus (GBS) is a type of bacteria. This bacteria is found in 30% of women. Though GBS infection is common, it does not primarily cause any major problems in adults. However, GBS infection is a potential life threat to newborns. This is why doctors perform a Group B strep test in the final trimester of pregnancy.

With the use of a cotton swab, your doctor will collect a sample from your vagina and rectum. This swab sample is then examined in the laboratory for infections. If the risk is high, doctors provide expecting moms with antibiotics during labour to avoid complications to the newborn. GBS screening can be done in 36-37 week of the pregnancy.

Nonstress Test (NST)

One of the most vital tests during third trimester pregnancy is a nonstress test. It is advised to women in case of a high-risk pregnancy. If your baby is not moving normally or if you are past your due date, this test may be advised to you. Like stress tests in adults, it is done to check the fetal movement and heart rate. However, it is called non-stress because no stress is applied to the fetus.

The doctor may strip a fetal monitor over your abdomen for examination. In many cases, the test does not show results as the baby is sleeping. Then the doctor gently tries to wake up the baby.

Contraction Stress Test

Similar to NST, a contraction stress test is also done to measure fetal heart rate. However, in this test, some stress is exposed to the fetus. This stress is applied to the fetus either by nipple stimulation or through Pitocin. Doctors administer oxytocin (a type of hormone secreted during childbirth) to pregnant women. During contractions, the blood flow to the placenta slows down.

During this test, if the heart rate of the fetus remains stable even during low blood flow, it implies that the placenta is functioning normally. However, if it does not, then the doctor gets an idea about the baby’s response. This way they can prepare for safe delivery by determining how the baby will react to contractions during delivery.

Biophysical profile

A biophysical profile is the combination of an NST and ultrasound. This is performed for a better evaluation of fetal health.


This test is indicated if the doctor believes that there is a possibility of bacterial infection to the baby. This infection is known as chorioamnionitis. In this test, the doctor will use a lengthy needle and insert it through your abdomen to the uterus.

They will simultaneously use an ultrasound to ensure that the needle does not touch the fetus. This needle is used to take a sample of amniotic fluid (the fluid surrounding the fetus). Later, the fluid is tested in the laboratory for infections.

Check out the article #LadiesAndBabies: Third Trimester of Pregnancy to know what happens to you and your baby during the third trimester.

Additional Third Trimester Scans And Tests

Besides the tests mentioned above, some common examinations will be a part of your routine visit. These examinations are equally important to confirm the health of the baby.

Physical assessment: Your doctor will measure your weight, fundal height and blood pressure.

Blood tests: You will be expected to take a blood test during pregnancy third trimester to check for iron deficiency, glucose screening and the presence of sexually transmitted diseases (STDs).

Urine tests: You may be asked to give a sample of your urine. This sample will be examined for signs of infections.

Things to Remember for Third Trimester Scans and Tests

We are certain you may be very overwhelmed for your baby’s arrival. But the importance of clinical evaluations is at a peak at this time. Consider the following while taking tests during the third trimester pregnancy.

When is it done? – Weeks 35-37 are ideal for most of the tests.

Is there a risk? – No, these tests and scans are majorly safe and do not have any side-effects. However, Amniocentesis may involve some risk. Ask your doctor for the same.

How do I prepare? – No additional preparations are needed.

Do these tests hurt? – No, you may expect the blood test during pregnancy third trimester to hurt just a little.

What to expect after the tests? – You will be asked to wait for the reports for proceedings.

What is Your Learning?

Third trimester scans and tests are of great importance as they prepare the healthcare team, your family, your baby and you, for a healthy delivery. Make sure to talk to your healthcare provider in case of any unusual symptoms.

Watch out for this space at LadiesAndBabies for more on pregnancy, women and child health.

Also, read about Important Pregnancy Screening Tests You Cannot Miss

For more information or free personalized guidance, speak to a Credihealth medical expert at +918010994994.

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