Growth Scan During Pregnancy: What It Reveals

A growth scan during pregnancy is an ultrasound that checks your baby’s size, weight, development, and overall wellbeing.

Pregnancy is filled with exciting milestones, and one of the most anticipated moments for many parents is seeing their baby during an ultrasound scan.

While early pregnancy scans focus on confirming the pregnancy and checking the baby’s anatomy,

growth scans performed later in pregnancy provide valuable information about how your baby is developing inside the womb.

Quick Answer

A growth scan is an ultrasound examination performed during pregnancy to assess your baby’s growth, estimate fetal weight, evaluate amniotic fluid levels, check the baby’s position, and monitor overall fetal well-being. Growth scans help healthcare providers identify babies who may be growing too slowly or too quickly and guide decisions about ongoing pregnancy care.

If your healthcare provider has recommended a growth scan, you may naturally wonder:

“Why do I need this scan?”

“Is something wrong with my baby?”

“What exactly does the scan reveal?”

As a women’s health physiotherapist, these are some of the most common questions I hear from expectant mothers.

Fortunately, in many cases, growth scans simply provide reassurance that the baby is growing well.

Understanding what happens during a growth scan can help reduce anxiety and allow you to feel more informed about your pregnancy journey.

Key Takeaways

Growth scans assess much more than your baby’s size and provide valuable information about overall fetal well-being.
During a growth scan, measurements such as head circumference, abdominal circumference, and femur length are used to estimate fetal weight.
Growth scans can help identify fetal growth restriction, excessive fetal growth, and abnormalities in amniotic fluid levels.
Doppler ultrasound studies may be performed to assess blood flow between the placenta and the baby, especially in high-risk pregnancies.
Growth scans provide estimates rather than exact measurements, so healthcare providers focus on growth trends over time.
Most growth scans provide reassurance and help guide decisions regarding pregnancy management and birth planning.
Additional growth scans are common in high-risk pregnancies and do not automatically indicate that something is wrong.

What Is a Growth Scan?

A growth scan is a specialised ultrasound examination designed to monitor fetal growth and development.

Unlike the detailed anomaly scan performed around 18 to 22 weeks, a growth scan primarily focuses on how the baby is growing over time.

Growth scans are commonly performed during the third trimester, although timing varies depending on individual pregnancy circumstances.

The purpose of the scan is not simply to measure size.

Instead, healthcare providers assess several aspects of fetal well-being to ensure that the pregnancy is progressing normally.

Growth scans often become particularly important in pregnancies considered high risk.

When Is a Growth Scan Performed?

There is no single schedule that applies to every pregnancy.

Some women may never require a growth scan beyond routine ultrasounds.

Others may undergo multiple scans during pregnancy.

Growth scans are frequently performed:

Between 28 and 32 weeks.
Around 36 weeks.
At regular intervals in high-risk pregnancies.

Your healthcare provider may recommend additional growth scans if concerns arise regarding fetal growth or maternal health.

Why Might Your Doctor Recommend a Growth Scan?

Photo- Magnific- Growth Scan During Pregnancy

There are several reasons why a healthcare provider may request a growth scan.

Common indications include:

Measuring Small or Large for Gestational Age

If fundal height measurements suggest that the baby is measuring smaller or larger than expected, an ultrasound can provide more accurate information.

High-Risk Pregnancy

Women with certain medical conditions often require additional fetal surveillance.

Examples include:

Gestational diabetes.
High blood pressure.
Preeclampsia.
Kidney disease.
Autoimmune disorders.

Previous Pregnancy Complications

A history of fetal growth restriction, stillbirth, or preterm birth may increase the need for closer monitoring.

Twin or Multiple Pregnancy

Multiple pregnancies typically require more frequent growth assessments.

Reduced Fetal Movements

A noticeable reduction in fetal movements may prompt ultrasound evaluation.

Importantly, needing a growth scan does not automatically mean that there is a problem.

Very often, the scan simply confirms that everything is progressing normally.

What Measurements Are Taken During a Growth Scan?

During the scan, the sonographer measures specific fetal body parts.

These measurements help estimate fetal size and growth patterns.

Common measurements include:

Head Circumference (HC)

Head circumference measures the size of the baby’s head.

This measurement helps assess brain growth and overall fetal development.

Biparietal Diameter (BPD)

The biparietal diameter measures the width of the baby’s head.

Abdominal Circumference (AC)

Abdominal circumference is one of the most important measurements during growth assessment.

Changes in abdominal growth may provide clues about placental function and nutritional supply.

Femur Length (FL)

Femur length measures the baby’s thigh bone.

This helps estimate fetal size and gestational age.

These measurements are combined using established formulas to estimate fetal weight.

How Accurate Is a Growth Scan?

Many parents are surprised to learn that growth scans provide estimates rather than exact measurements.

Ultrasound-estimated fetal weight is useful, but it is not perfect.

There is always a margin of error.

For this reason, healthcare providers usually place greater emphasis on growth trends across multiple scans rather than relying on a single measurement.

Serial assessments often provide a clearer picture of fetal growth.

What Can a Growth Scan Reveal?

Growth scans provide much more information than simply estimating the baby’s size.

1. Whether the Baby Is Growing Appropriately

One of the main objectives of growth scanning is determining whether fetal growth follows an expected pattern.

Some babies naturally grow more slowly or more quickly than others.

Healthcare providers evaluate whether the baby’s growth pattern remains appropriate over time.

2. Fetal Growth Restriction (FGR)

Growth scans help identify babies who may not be reaching their growth potential.

Fetal growth restriction occurs when the fetus fails to grow as expected.

Early identification allows healthcare providers to increase surveillance and determine the safest timing for delivery. (Chew et al. 2024)

3. Excessive Fetal Growth

Growth scans may also reveal that the baby is growing larger than expected.

Large-for-gestational-age babies are more common in pregnancies affected by:

Gestational diabetes.
Maternal obesity.
Excessive pregnancy weight gain.

Identifying excessive growth helps healthcare providers plan labour and delivery appropriately.

Amniotic Fluid Assessment

Growth scans routinely evaluate amniotic fluid levels.

Amniotic fluid plays an essential role in fetal development by cushioning the baby and supporting normal growth.

The sonographer may identify:

Low Amniotic Fluid (Oligohydramnios)

Reduced fluid levels may sometimes be associated with:

Placental insufficiency.
Rupture of membranes.
Certain maternal medical conditions.

Excessive Amniotic Fluid (Polyhydramnios)

High fluid levels may occasionally occur in pregnancies complicated by gestational diabetes or other conditions.

Many women with mild fluid abnormalities still have healthy pregnancies, but additional monitoring may be required.

Doppler Ultrasound: Looking at Blood Flow

Some growth scans include Doppler studies.

A Doppler ultrasound measures blood flow through specific blood vessels.

Healthcare providers commonly assess:

Umbilical artery blood flow.
Middle cerebral artery blood flow.
Uterine artery blood flow.

Doppler studies are especially valuable in pregnancies affected by fetal growth restriction because they provide information about placental function and fetal adaptation.

Research shows that Doppler ultrasound improves surveillance in high-risk pregnancies. (Alfirevic et al. 2017)

A Physiotherapist’s Perspective: Coping With Scan Anxiety

Waiting for growth scan results can be emotionally challenging.

Many expectant mothers tell me that they feel anxious for several days before their appointment.

A few strategies may help:

Limit excessive internet searching.
Continue medically approved physical activity.
Practise diaphragmatic breathing.
Attend antenatal physiotherapy sessions.
Discuss concerns openly with your healthcare provider.

Remember that most growth scans provide reassurance rather than identify serious concerns.

Are Growth Scans Safe During Pregnancy?

Current evidence indicates that medically indicated diagnostic ultrasound performed by trained healthcare professionals is safe during pregnancy when used appropriately.

Healthcare providers always aim to use ultrasound only when clinically necessary. (Torloni et al. 2009)

What Happens If the Baby Is Measuring Small?

One of the most common reasons for anxiety after a growth scan is hearing that the baby is “measuring small.”

However, a smaller measurement does not automatically mean that something is wrong.

Some babies are naturally small because of genetics.

Smaller parents often have smaller babies, and these babies may remain perfectly healthy throughout pregnancy.

Healthcare providers become more concerned when:

Growth slows significantly between scans.
Doppler blood flow studies become abnormal.
Amniotic fluid levels decrease.
Other signs of placental insufficiency are present.

When concerns arise, your healthcare provider may recommend:

Repeat growth scans.
Additional Doppler assessments.
Non-stress tests.
Biophysical profiles.
More frequent antenatal appointments.

The purpose of this monitoring is to ensure that the baby continues to receive adequate oxygen and nutrients.

What If the Baby Is Measuring Large?

Growth scans occasionally show that a baby is larger than expected for gestational age.

This may occur because of:

Gestational diabetes.
Maternal obesity.
Previous large baby.
Genetic factors.
Excessive maternal weight gain.

A larger baby does not automatically mean that delivery complications will occur.

However, identifying excessive growth allows healthcare providers to discuss:

Birth planning.
Labour management.
Delivery options.
Additional monitoring if required.

It is important to remember that ultrasound estimates are not exact and should always be interpreted alongside clinical assessment (Beta et al. 2019)

Can a Growth Scan Predict Birth Weight?

Many parents want to know exactly how much their baby weighs.

Unfortunately, no ultrasound can predict birth weight with complete accuracy.

Growth scans provide an estimate.

Factors such as fetal position, maternal body composition, and operator experience can influence measurements.

Research suggests that ultrasound-estimated fetal weight becomes less precise at the extremes of fetal size.

For this reason, healthcare providers generally focus on overall growth trends rather than a single estimated weight.

How Often Are Growth Scans Repeated?

The frequency of growth scans depends on individual pregnancy circumstances.

Women with uncomplicated pregnancies may require only one scan or none at all after the routine anomaly scan.

However, women with high-risk pregnancies may undergo serial monitoring.

Typical situations requiring repeated scans include:

Pregnancy Situation	Typical Monitoring Frequency
Suspected fetal growth restriction	Every 2 to 4 weeks
Twin pregnancy	Every 2 to 4 weeks
Gestational diabetes	Individualised monitoring
Hypertension or preeclampsia	Regular surveillance
Previous fetal growth restriction	Increased monitoring

Your healthcare provider will determine the most appropriate schedule based on your specific needs.

Can Growth Scans Influence Delivery Decisions?

Yes.

Growth scan findings may influence decisions regarding:

Timing of delivery.
Need for induction of labour.
Requirement for additional fetal surveillance.
Mode of birth.

For example:

Severe fetal growth restriction may prompt earlier delivery.
Significant Doppler abnormalities may require intensive monitoring.
Persistent breech presentation identified during a growth scan may alter birth planning.

Healthcare providers always consider multiple factors before recommending any intervention.

What Growth Scans Cannot Tell You

Although growth scans provide valuable information, they also have limitations.

Growth scans cannot guarantee:

A complication-free labour.
Perfect health after birth.
Exact birth weight.
Future developmental outcomes.
The exact timing of labour.

Understanding these limitations can help parents maintain realistic expectations and reduce unnecessary anxiety.

Myths vs Facts About Growth Scans During Pregnancy

Myth: If my doctor recommends a growth scan, something must be wrong with my baby.

Fact: Growth scans are often performed as a precaution, especially in high-risk pregnancies, and frequently provide reassurance that the baby is growing well.

Myth: Growth scans can predict my baby’s exact birth weight.

Fact: Ultrasound provides an estimated fetal weight, but there is always a margin of error. Healthcare providers focus more on growth trends over time than a single measurement.

Myth: A baby measuring small on a growth scan always has a problem.

Fact: Some babies are naturally small because of genetics. Additional assessments help distinguish healthy small babies from those with fetal growth restriction.

Myth: More ultrasound scans are harmful to the baby.

Fact: Current evidence suggests that medically indicated diagnostic ultrasound performed by trained healthcare professionals is safe during pregnancy when used appropriately.

Myth: If my baby measures large, I will definitely need a caesarean section.

Fact: Many women carrying larger babies have successful vaginal births. Delivery recommendations depend on multiple factors, not fetal size alone.

Myth: A normal growth scan guarantees a problem-free pregnancy and birth.

Fact: Growth scans provide valuable information about fetal well-being, but no test can predict every possible pregnancy complication or birth outcome.

Can You Improve Your Baby’s Growth?

This is one of the most frequently asked questions.

In many situations, fetal growth is influenced by factors that parents cannot control.

However, supporting a healthy pregnancy remains important.

Recommendations include:

Attend all antenatal appointments.
Eat a balanced, nutrient-rich diet.
Avoid smoking and alcohol.
Follow medical advice regarding chronic health conditions.
Stay physically active if medically permitted.
Monitor fetal movements.

As a physiotherapist,

I encourage expectant mothers to remain physically active during uncomplicated pregnancies because movement supports overall maternal health and well-being. (Mottola et al. 2018)

Questions You May Want to Ask Your Doctor

Consider asking:

Is my baby’s growth within the normal range?
Will I need another growth scan?
Are my amniotic fluid levels normal?
Was Doppler blood flow normal?
Will scan findings affect my birth plan?
Should I monitor fetal movements more closely?
What symptoms should prompt urgent review?

Preparing questions in advance often helps parents feel more informed and reassured.

Final Thoughts

Growth scans provide valuable information about your baby’s growth and overall well-being during pregnancy. Although being advised to undergo additional scans can feel stressful, these assessments often provide reassurance and help healthcare providers identify concerns early. Remember that every baby grows differently, and regular monitoring helps ensure the safest possible outcome for both mother and baby.

Conclusion

Growth scans play an essential role in modern maternity care.

These scans provide valuable information about fetal growth, placental function, amniotic fluid levels, and overall fetal well-being.

Although being referred for a growth scan can sometimes create anxiety, the majority of scans simply provide reassurance that the baby is developing appropriately.

As a women’s health physiotherapist,

I encourage expectant mothers to attend all scheduled appointments, ask questions whenever they feel uncertain, and remember that every pregnancy follows its own unique journey.

Frequently Asked Questions (FAQs)

1. What is the purpose of a growth scan during pregnancy?

A growth scan helps assess your baby’s growth, estimated weight, amniotic fluid levels, position, and overall well-being during pregnancy. It also helps identify babies who may be growing too slowly or too quickly.

2. When is a growth scan usually performed?

Growth scans are commonly performed during the third trimester, often between 28 and 32 weeks or around 36 weeks of pregnancy. However, the timing may vary depending on individual pregnancy circumstances.

3. Does needing a growth scan mean something is wrong with my baby?

No. Growth scans are frequently recommended as a precaution, especially in high-risk pregnancies, and often provide reassurance that the baby is developing normally.

4. How accurate are growth scans in estimating birth weight?

Growth scans provide an estimate rather than an exact birth weight. Although ultrasound is useful for monitoring growth trends, there is always a margin of error in fetal weight estimation.

5. Are growth scans safe during pregnancy?

Current evidence suggests that medically indicated diagnostic ultrasound performed by trained healthcare professionals is safe during pregnancy when used appropriately.

6. Can growth scan results affect my birth plan?

Yes. Findings such as fetal growth restriction, excessive fetal growth, breech presentation, or abnormal Doppler blood flow may influence decisions regarding labour, delivery timing, and ongoing pregnancy management.

Stay tuned with us for more health related topics.

Medical Disclaimer!

This article has been reviewed and written under the guidance of our Head Physiotherapist, Dr. Kruti Raj (PT, MUHS,CPT,CMPT). The information shared is intended for educational purposes only and should not be considered a substitute for personalized medical advice, diagnosis, or treatment.

Please consult us or any other qualified healthcare professional before beginning any exercise program, especially if you are experiencing pain, recovering from injury, or managing a medical condition.