Difference Between NT Scan and Anomaly Scan

Both the anomaly scan and the nuchal translucency (NT) scan are types of ultrasound scans used during pregnancy to assess the health and development of the fetus. These scans play crucial roles in monitoring fetal development and detecting potential issues early. Both NT scans and anomaly scans are safe, routine procedures in prenatal care when conducted by trained professionals, helping monitor fetal development without known risks to the baby.

Comparative table : Differences between the NT scan and anomaly scan

Browse best Scrubs Collection

What is an NT Scan?

The NT (nuchal translucency) scan is typically performed between weeks 11 and 14 of pregnancy. It is a non-invasive ultrasound procedure that measures the clear (translucent) space in the tissue at the back of the baby's neck. This measurement helps assess the risk of chromosomal abnormalities, particularly Down syndrome (Trisomy 21) and other genetic disorders.

Timing and Purpose

• Typically performed between weeks 11 and 14 of pregnancy.
• Aimed at measuring the nuchal translucency (NT), which is the clear (translucent) space at the back of the baby's neck.
• Helps assess the risk of chromosomal abnormalities, particularly Down syndrome (Trisomy 21), and other genetic conditions.

Procedure

• Conducted via a non-invasive ultrasound procedure.
• Involves using ultrasound technology to measure the thickness of the nuchal translucency.
• Sometimes combined with blood tests (such as PAPP-A and hCG levels) to provide a risk assessment score.

Risk Assessment

• Provides a risk score based on NT measurement and additional blood test results.
• Higher NT measurement, along with abnormal blood test results, may indicate an increased likelihood of chromosomal abnormalities.

Safety and Comfort

• Safe and painless procedure for both the mother and the fetus.
• Typically performed transabdominally using ultrasound gel and a handheld device.
• Generally takes about 10-20 minutes, depending on fetal position and cooperation.

Explore All Women's Scrub

What is an Anomaly Scan?

The anomaly scan, also known as the mid-pregnancy ultrasound scan or the fetal anomaly ultrasound, is typically performed between weeks 18 and 22 of pregnancy. Unlike the NT scan, which focuses primarily on assessing chromosomal abnormalities, the anomaly scan is a more comprehensive examination aimed at detecting structural abnormalities in the developing fetus.

Timing and Purpose

• Typically performed between weeks 18 and 22 of pregnancy, ideally around 20 weeks.
• Also known as the mid-pregnancy ultrasound scan or fetal anomaly ultrasound.
• Aimed at a detailed assessment of fetal anatomy and development to detect structural abnormalities.

Procedure and Imaging

• Typically performed transabdominally using ultrasound gel and a handheld device.
• In some cases, a transvaginal ultrasound may be used for better visualization, especially in early or difficult-to-image pregnancies.
• Takes longer than the NT scan, usually around 30-45 minutes, due to the comprehensive nature of the examination.

Risk assessment

It involves detecting structural abnormalities in fetal anatomy. This comprehensive ultrasound evaluates organs, limbs, and the umbilical cord for any developmental issues. Identification of abnormalities allows for timely intervention or preparation before birth, supporting informed decision-making and optimizing pregnancy management.

Safety and Comfort:

• Safe and non-invasive procedure for both the mother and the fetus.
• Painless for the mother, although some discomfort may occur due to the need for a full bladder for optimal imaging.

Shop the Best Lab Coats from Here!

Key differences between the NT scan and anomaly scan

• Timing: NT scan is typically done between weeks 11-14 to assess nuchal translucency and chromosomal abnormalities risk, whereas the anomaly scan occurs around weeks 18-22 to examine detailed fetal anatomy.
• Focus: NT scan primarily assesses nuchal translucency thickness and genetic risk, while the anomaly scan thoroughly evaluates fetal anatomy for structural abnormalities and developmental issues.
• Diagnostic Nature: NT scan provides a risk assessment, while anomaly scan aims for detailed anatomical detection, aiding in early intervention if abnormalities are found.