How Foetal Medicine Monitors and Treats Foetal Growth Restriction (FGR)
Among many pregnancy complications, foetal growth restriction (FGR) is the most common, affecting an estimated 10% of pregnancies worldwide. If left untreated, it can pose significant health risks to both the mother and baby and, in worse cases, lead to stillbirth or neonatal mortality. This condition generally occurs when a foetus in the womb fails to achieve its full genetically determined growth, often due to placenta dysfunction, maternal health, or other complications.
While this condition can be alarming, early foetal growth restriction (FGR) diagnosis and treatments can potentially ensure better outcomes for affected pregnancies. Read on to learn how foetal medicine can help monitor and treat foetal growth restriction.
What is Foetal Growth Restriction (FGR)?
Foetal growth restriction (FGR), also called intrauterine growth restriction (IUGR), refers to the condition where a foetus is smaller than expected for the gestational age (number of weeks of pregnancy). It’s generally described as an approximate weight of a baby less than the 10th percentile for its age.
It's been found that FGR can begin at any stage of pregnancy. This medical condition affects not only the weight of a foetus but also the overall size of the infant and the growth of its cells, tissues, and organs.
Usually, pregnancies are affected by two types of foetal growth restriction:
Symmetrical or Primary FGR: The baby’s body parts, including the head, are proportionally small, often due to genetic issues or early pregnancy complications.
Asymmetrical or Secondary FGR: In this condition, the baby’s head and other body parts measures normally, but the abdomen is small.
Knowing the Symptoms of Foetal Growth Restriction (FGR)
Most people don’t notice the signs of a baby not growing in the womb. However, you might feel that your belly isn’t as big as it should be or your foetus is too small during ultrasounds. If you have such a feeling, it’s advisable to ask your healthcare provider for a foetal growth restriction (FGR) diagnosis.
What Causes Foetal Growth Restriction?
Many factors can contribute to the increased risk of FGR, including maternal, foetal, and placental causes. It could be caused when the placenta fails to attach well, or there is limited blood flow through the umbilical cord. Knowing the root cause of FGR will help in providing the appropriate management and prognostication of foetal growth restriction. The below discussed are some common causes of foetal growth restriction:
Maternal Factors
High blood pressure, hypertension, or preeclampsia
A large amount of excess weight (obesity)
Poor nutrition during pregnancy
Smoking, alcohol consumption, or drug use
Long-term kidney or lung disease
Too few red blood cells or anaemia
Autoimmune conditions, like lupus
Very low weight
Foetal Factors
Genetic or chromosomal disorders such as Down syndrome
Birth defects, like heart defects
Infections like rubella or toxoplasmosis
Multiple pregnancies (twins, triplets, etc.)
Placental Factors
Placental insufficiency leading to failure of delivery of adequate nutrients and oxygen to the foetus
Abnormal placental attachment or structure
How does Foetal Medicine Diagnose and Monitor Foetal Growth Restriction (FGR)?
The reason why regular prenatal examination and monitoring are important is to make sure your baby is growing optimally in size. Foetal medicine employs various diagnostic tools and monitoring techniques to accurately detect whether your pregnancy is affected by foetal growth restriction.
Diagnostic Tools for FGR
During pregnancy, different ways are used to estimate the size of your baby, such as:
Fundal Height: Your doctor will measure the size of your belly from the top of your pubic bone to the uterus (fundus) top to check the fundal height. Measured in centimetres, the fundal height should be the same as the number of weeks of pregnancy post the 20th week.
Weight: Gynaecologists also measure expecting mother's weight during each prenatal visit and calculate the weight gain. Poor maternal weight gain could be an indirect indicator that their foetus is not gaining optimal weight.
If the size and weight of your baby is less than expected your healthcare provider might recommend the tests for identification of the cause of growth restriction and to monitor the foetal growth e. g
Ultrasound Imaging: During ultrasounds, gynaecologists move a probe across the expecting women’s bellies, allowing sound waves to create a picture of the foetuses. These pictures are used to measure and estimate the size and weight of the fetus. In addition, ultrasounds are used to evaluate blood flow from the placenta through the umbilical artery and other fetal and maternal vessels. Abnormal flow patterns can suggest placental insufficiency, a leading cause of FGR.
Maternal Blood Tests: Several maternal blood tests might also be performed to detect placental dysfunction, infections, or preeclampsia, all associated with FGR.
Amniocentesis: This procedure can help find out the congenital causes of FGR. What your doctor will do is insert a needle into your uterus through your skin to draw a small amount of amniotic fluid from your womb. This sample of amniotic fluid is tested for irregularities, such as infections or other conditions contributing to FGR.
Monitoring Techniques for FGR
When diagnosed with FGR, your healthcare provider might employ the below-outlined techniques for monitoring foetal growth restriction:
Serial Ultrasounds: You might have to undergo a series of ultrasounds after certain intervals to track the growth trajectories of your foetus. It will help your doctor to identify deviations from normal weight and size patterns.
Non-Stress Tests (NST): These tests will help monitor the fetal heart rate, ensuring that your baby is responding well to in-utero conditions.
Biophysical Profile (BPP): This FGR monitoring procedure combines ultrasound with NST to evaluate the movement, breathing, muscle tone, and amniotic fluid levels of your foetus.
Foetal Medicine Management and Treatment of Foetal Growth Restriction
Now that you have been diagnosed with FGR, your first question to your healthcare provider might be how is foetal growth restriction treated. Foetal medicine offers comprehensive management and treatment strategies for FGR, which are used depending on how serious the FGR is, gestation week, and other risk factors.
The primary step in the management and treatment of FGR might include frequent monitoring, as discussed above. Next, your healthcare provider might use the following strategies:
Tracking Foetal Movements: Your gynaecologist might ask you to keep track of foetal movements, such as counting how many times your foetus kicks your belly, as decreased activity can signal a need for medical attention.
Early Delivery: In severe cases of foetal growth restriction, which is when the pregnancy isn’t developing, or your foetus is at a significant health risk, labour might be induced early before completing 37 weeks of gestation. In such a case, early delivery via C-section is recommended because severe FGR could lead to complications, such as foetal distress or stillbirth, due to insufficient oxygen and nutrient supply. But why cesarean section and not vaginal delivery? It’s because vaginal delivery can stress growth-restricted infants.
Corticosteroid Medications: In growth restricted fetuses when there is need for early delivery ,in such a case, corticosteroids are commonly administered to help mature your baby’s lungs By enhancing lung maturity, these medicines can significantly improve your baby’s chances of survival while reducing the risk of complications such as respiratory distress syndrome.
All-in-All
Many factors can increase the risk of your baby not gaining ideal weight when in your womb. Don’t worry! Fetal medicine help you in detecting fetal growth restriction in your baby on time by using various diagnostic tools. If FGR is diagnosed, you will be continuously monitored and treated using an approach which is appropriate for your condition.
When worried your baby is not growing optimally, don’t wait. Just book an appointment with an expert fetal medicine specialist at your nearest super-specialty hospital for FGR diagnosis and treatment, if needed!
FAQs
1. How often are ultrasounds performed for FGR monitoring?
For FGR, ultrasounds are typically performed every 2-4 weeks, but this can vary based on the severity and clinical judgement.
2. What are the common causes of FGR?
Common causes include placental insufficiency, maternal health issues (e.g., hypertension, diabetes), and certain infections or genetic conditions.
3. Can FGR be treated during pregnancy?
Treatment focuses on managing underlying maternal conditions, optimizing maternal health, and sometimes early delivery if the foetus is at risk.
4. What lifestyle changes can help manage FGR?
Improving maternal nutrition, reducing stress, avoiding smoking and alcohol, and regular prenatal care can support better outcomes.
5. When is early delivery recommended in FGR cases?
Early delivery may be recommended if the foetus shows signs of distress, poor growth progression, or abnormal Doppler findings.
Citations
Colella, M., Frérot, A., Novais, A. R. B., & Baud, O. (2018). Neonatal and Long-Term Consequences of Fetal Growth Restriction. Current Pediatric Reviews, 14(4), 212–218. https://doi.org/10.2174/1573396314666180712114531
Dall’Asta, A., Brunelli, V., Prefumo, F., Frusca, T., & Lees, C. C. (2017). Early onset fetal growth restriction. Maternal Health Neonatology and Perinatology, 3(1). https://doi.org/10.1186/s40748-016-0041-x
Pels, A., Beune, I. M., Van Wassenaer‐Leemhuis, A. G., Limpens, J., & Ganzevoort, W. (2019). Early‐onset fetal growth restriction: A systematic review on mortality and morbidity. Acta Obstetricia Et Gynecologica Scandinavica, 99(2), 153–166. https://doi.org/10.1111/aogs.13702
Pugh, S., Ortega‐Villa, A., Grobman, W., Newman, R., Owen, J., Wing, D., Albert, P., & Grantz, K. (2018). Estimating gestational age at birth from fundal height and additional anthropometrics: a prospective cohort study. BJOG an International Journal of Obstetrics & Gynaecology, 125(11), 1397–1404. https://doi.org/10.1111/1471-0528.15179
Sharma, D., Shastri, S., & Sharma, P. (2016). Intrauterine growth restriction: antenatal and postnatal aspects. Clinical Medicine Insights Pediatrics, 10. https://doi.org/10.4137/cmped.s40070
Tsikouras, P., Antsaklis, P., Nikolettos, K., Kotanidou, S., Kritsotaki, N., Bothou, A., Andreou, S., Nalmpanti, T., Chalkia, K., Spanakis, V., Iatrakis, G., & Nikolettos, N. (2024). Diagnosis, Prevention, and Management of Fetal Growth Restriction (FGR). Journal of Personalized Medicine, 14(7), 698. https://doi.org/10.3390/jpm14070698
