Pregnancy is a time of joy and anticipation for expectant parents. With modern medical technology, various tests and screenings are done throughout pregnancy to ensure the health of both the mother and the developing fetus.

One of the most critical of these diagnostic tests is ultrasound, which uses sound waves to produce images of the developing fetus.

What is Third Trimester Ultrasound?

During pregnancy, an ultrasound scan is typically carried out in three stages: the first trimester, the second trimester, and the third trimester. The third trimester is the last stage of pregnancy, occurring from week 28 until birth.

An ultrasound scan performed during this time is referred to as an early third trimester ultrasound.

Reasons for Early Third Trimester Ultrasound

The early third trimester ultrasound is an essential examination that provides obstetricians with valuable information about the health and growth of the fetus, as well as the overall well-being of the mother.

Here are some of the reasons why early third trimester ultrasound is performed:.

1. Fetal Growth Assessment

One of the most critical aspects of a third-trimester ultrasound is for the medical professionals to check on the growth of the fetus. Infant growth is determined by measuring the diameter of the developing baby’s head, abdomen, and femur.

Scanning fetal growth is crucial since inadequate growth can be a sign of fetal malnutrition, abnormalities in the umbilical cord or placenta, or other health concerns.

2. Placenta Assessment

The early third trimester ultrasound is critical for assessing the condition of the placenta. This can reveal problems such as placental insufficiency or preeclampsia, which are conditions linked to premature birth or fetal growth problems.

3. Amniotic Fluid Assessment

Amniotic fluid in the womb protects the developing fetus from injury and infection while also aiding in fetal movement. A low amniotic fluid level, a condition called oligohydramnios, may indicate placental insufficiency or impaired fetal growth.

On the other hand, the excess of amniotic fluid, termed polyhydramnios, may cause preterm labor or preterm rupture of membranes.

4. Multiple Gestation Pregnancy Assessment

During the third trimester of pregnancy, ultrasound scans help doctors assess the health of both the mother and all fetuses, particularly in cases of twin or multiple pregnancies.

An early third trimester ultrasound is necessary to determine the position of the fetuses in the womb and identify complications such as twin-twin transfusion syndrome, where the blood flows unequally between twin fetuses, or an incompetent cervix, where the cervix may open before a term is reached.

5. Preterm Labor Assessment

Preterm labor means the onset of labor before term, which is the 37th week of pregnancy. The causes of prematurity can vary, from infections of the placenta, cervico-uterine incompetency, and premature rupture of membranes.

An early third trimester ultrasound can be used to monitor cervical length, and determine whether a mother is at high risk of preterm labor or delivery.

6. Identifying Anomalies

The early third trimester ultrasound can help identify anomalies in the fetus that may require extra attention or intervention.

This ultrasound can look for certain physical traits or conditions, including heart abnormalities, spina bifida, and brain malformations, which benefit from early detection and establishment of a management plan.

7. Confirmation of Fetal Positioning

The early third trimester ultrasound is critical to ensure that the baby is in the optimal position for delivery, i.e., a head down position. Knowing the position allows the care providers to determine the best delivery route to avoid any complications.

8. Evaluation of Cervical Length

The length of a woman’s cervix can be a predictor of preterm birth if it shortens before the end of the pregnancy. A transvaginal ultrasound is performed at 24 weeks to evaluate cervical length, which can be rechecked at the early third trimester scan.

9. Confirmation of Fetal Sex

Parents may choose to have an early third-trimester ultrasound to reveal the sex of their baby if they were not able to do so during the second trimester ultrasound. This can assist parents in planning for a specific sex baby or planning a nursery.

10. Preparation for Delivery

Parents may wish to mentally and physically prepare for delivery by understanding their baby’s estimated weight and position, as well as the baby’s overall health and wellbeing before entering labor and delivery.

An early third-trimester ultrasound enables parents to make informed decisions about their preferred route of delivery and plan for the baby’s arrival.

Conclusion

In conclusion, the early third trimester ultrasound is a critical component of prenatal care and helps detect medical concerns that need prompt attention.

The scan provides healthcare providers with valuable information about fetal development, growth and can detect possible anomalies such as spina bifida, clubfoot, and Down Syndrome. Early third-trimester ultrasounds provide parents’ peace of mind from understanding the baby’s estimated weight and position, the baby’s overall health, and potential complications that may arise during the remaining weeks of pregnancy.