Pregnancy ultrasound month by month

Ultrasound Checkups During Pregnancy: 101

Most moms think of an ultrasound as a way of determining the gender of their baby. Thus, the first ultrasound checkup is a big day that is full of surprises and overflowing happiness.

This isn’t the only purpose of prenatal ultrasound though. As one of the basic and most important procedures an expectant mom goes through, ultrasound checkups can be the first line of defense against potential issues during pregnancy and greatly helps monitor the health of both the mom and her baby.

 This article gives an overview about the importance of prenatal ultrasound and what moms should expect each time they undergo the procedure.

 Prenatal Ultrasound: Functions & Benefits

 A prenatal ultrasound is usually conducted on the 20th week of pregnancy. The first ultrasound checkup is used to determine a few basic things, such as the gender of the baby and the possible due date of the mother.

 Ultrasound imaging is non-invasive and painless. During a prenatal ultrasound, the mother will lie on a table and the doctor applies a thin coating of ultrasound gel on her stomach, which is designed to ensure the accuracy of the ultrasound waves. The most important part of an ultrasound machine is the transducer which transmits high-frequency sound waves to the uterus. The sound waves then send signals back to the machine to generate images of the baby.

 To find out more on how ultrasound works check this article.

Prenatal ultrasound has many other functions in ensuring the health of the mother and her child. They include the following:


  • Determine whether the mother is carrying multiples.
  • Monitoring the location and state of the placenta – the organ that provides oxygen and nutrients to the developing fetus and removes the waste products from the baby’s blood.
  • Tracking the level of amniotic fluid that surrounds the baby in the womb. Prenatal ultrasound can determine whether the fluid levels are health or not.
  • Determining the baby’s position which is very important during birth.
  • Determining the baby’s expected weight.
  • Identify congenital problems with the baby.


Types of Ultrasounds for Pregnancy Tracking

There are different kinds of ultrasound machines used for pregnancy, such as the following:

Standard Ultrasound – this is the most common type of ultrasound used for pregnancy that produces two-dimensional images of the baby.

Transvaginal Scan – often used for high-risk pregnancies, the obstetrician may perform an ultrasound check earlier (less than 10 weeks of pregnancy) than a standard ultrasound. In this case, transvaginal scan is used wherein the transducer is inserted into the vagina to perform a scan.

Fetal Echocardiography – this type of ultrasound is used to detect potential problems in the developing heart of the fetus. The doctor may recommend a fetal echocardiography if he sees an irregularity in the heartbeat of the baby or if any of the parents has a history of heart problems.

3-D Ultrasound – a modern ultrasound that makes use of a specially designed transducer and computer software to produce three-dimensional images of the baby.

4-D Ultrasound – technically called dynamic 3-D ultrasound, this machine gives a more realistic view of the baby. Parents can enjoy seeing their baby in action. Apart from this, the 4-D Ultrasound does not offer diagnostic advantage over the standard ultrasound.

Doppler Ultrasound – this is used for women who suffer from gestational diabetes. Performed during the last few weeks in the third trimester, a Doppler ultrasound measures blood flow and blood pressure in the womb.

Ultrasound Checkups: A Trimester-by-Trimester Guide

First Trimester Ultrasound Check Up

The first ultrasound checkup takes place around 6-8 weeks of pregnancy. At this stage, the baby is still very small and is closer to the birth canal than the abdomen. Thus, the doctor is likely to perform a transvaginal ultrasound as it will be difficult to see the baby using a standard ultrasound at this time.

During the first trimester, nuchal translucency (NT) test which involves another ultrasound between 11 and 13 weeks, to evaluate the baby’s risk of trisomy, Down syndrome or any other chromosomal abnormality. Further ultrasounds may also be performed to determine the mother’s due date more accurately.

Second Trimester  Ultrasound Check Up

This is the most thrilling part for most parents because on the second trimester, the gender of the baby is determined. Performed between weeks 18 to 20 of pregnancy, a standard ultrasound gives parents a long, detailed look of their baby.

The scan lasts for 20 to 45 minutes. The doctor will check the baby’s heart rate, and look for abnormalities in the brain, heart, kidneys, and liver. He or she will also examine the placenta, measure the amniotic fluid level, and count the fingers and toes, and make sure all of the baby’s organs are developing properly. 

Third Trimester  Ultrasound Check Up

The last ultrasound exam generally takes place at the 20th week of the mother’s anatomy scan. If the mother has gone past her due date, another ultrasound is performed to monitor the baby’s heart rate and measure the mother’s amniotic fluid level.  Other reasons why some parents ask more ultrasounds during the third trimester are to check the health of the placenta and ensure that the baby’s growth is on track.

For mothers suffering from gestational diabetes, the doctor may perform a Doppler ultrasound in the last weeks to determine if her baby is getting enough blood.

Prenatal Ultrasound Safety Concerns 

Ultrasounds are considered safe for the mother and her baby when used for medical purposes. It should be performed by a highly trained medical technician who should have gotten proper training in obstetrical ultrasound, accredited center by the American Institute of Ultrasound in Medicine.

Throughout pregnancy, a woman will be required to undergo ultrasound checkups to keep tab of her health and her baby’s. More than identifying the gender of the baby, ultrasounds are used to detect potential problems and ensure that the baby is developing properly. There are several kinds of ultrasounds for pregnancy, each one has its specific features and functions and may be used during the first, second and third trimesters. Getting ultrasound scans from a qualified technician is important to ensure accuracy of the readings.

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