Common Prenatal Tests during the Third Trimester

Common Prenatal Tests during the Third Trimester : While you may have undergone a myriad of prenatal tests early on in your pregnancy, the testing does not stop even when you’re already at the homestretch. In fact, the need for constant monitoring during this stage may be a higher as your baby gets ready to come out into the real world.

These third trimester tests will ensure that you and your baby are at your optimum health and well-being as you’re nearing labor and delivery.

While not all women are required to undergo these tests, here are some of the most common third trimester prenatal tests that may be given to you:

Ultrasound

Unlike the previous ultrasounds you’ve had that confirmed your pregnancy and your baby’s gender, the third-trimester ultrasound may be given to assess the baby’s size, growth, and more particularly, his or her position—which are all valuable information as you are nearing your due date.

An ultrasound may also be used to obtain a biophysical profile (BPP), which is a combination of tests that keeps tabs on your baby’s health. A BPP may be recommended if you are past your due date or have a high-risk pregnancy due to other health conditions.

Group B Streptococcus Screening

Group B streptococcus (GBS) is a type of bacteria that thrives in the female reproductive tract of up to 30 percent of healthy women, yet it usually does not cause any problems.
In some cases, however, it can lead to infection of the bloodstream, the urinary tract, or the placenta, which may put a newborn’s life at risk for infections such as pneumonia, meningitis, and sepsis.

A GBS screening, which is usually done at 35 to 37 weeks, is a simple test that involves taking a sample using a cotton swab from the vagina and from the rectum. The sample is then cultured in the laboratory to detect any presence of GBS. Once tested positive, you will be given antibiotics as you go into labor to reduce your baby’s chances of getting infected.

Nonstress Test

A nonstress test is usually done on a weekly basis for high-risk pregnancies from 28 to 32 weeks onward. However, the test can also be ordered anytime the baby is moving or kicking less frequently than is usual or if you are past your due date. In such cases, your doctor will need to ensure the condition of your baby while inside your womb through a nonstress test.

This test involves strapping a fetal monitor across your abdomen to measure the baby’s heart rate as he or she moves. On the other hand, your blood oxygen saturation levels may also be monitored during such time using a Welch Allyn SpO2 sensor to ensure that you are giving enough oxygen to your baby. The nonstress test is called such because it literally places no stress on your little one.

Amniocentesis

While this test is commonly performed in the second trimester to rule out fetal birth defects, it can also be recommended in the third trimester if you are at risk for premature delivery or if your baby is believed to have anemia. This is also required if you are diagnosed with chorioamnionitis, which is a uterine bacterial infection that may induce preterm labor.

Amniocentesis is an invasive third trimester test that involves the insertion of a hollow thin needle through the skin and into the uterus to extract a small sample of the amniotic fluid. Since this fluid contains cells released by the fetus, it can provide the doctor essential information regarding your baby’s health.

Amniocentesis can also help determine if your baby’s lungs have already matured despite your baby being delivered prematurely. This helps your doctor address the situation promptly by delivering treatment that speeds up your baby’s lung development.

Always Consider

If your doctor advises you to have some of these tests, try not to feel anxious about it. These will only ensure that your baby gets the best health possible once he or she arrives in this world.