Intrauterine growth restriction (IUGR) is a condition where the fetus is smaller than expected for the number of weeks of pregnancy. Smoking, alcohol consumption, low weight gain during pregnancy, anemia, previous preterm delivery or abortion can increase IUGR risk. IUGR can lead to memory and learning deficiencies and metabolic syndrome.
What Is Growth Retardation?
According to Stanford Children’s Health, Intrauterine Growth Restriction (IUGR) is a term used to describe a condition in which the fetus is smaller than expected for the number of weeks of pregnancy . This condition is also called as “fetal growth restriction” where the newborn baby is comparatively much smaller in size for the gestational age. Fetuses with IUGR are born as either as preterm babies – after 37 weeks of pregnancy or prematurely – before 37 weeks.
Physical Symptoms Of Fetus With IUGR
Diagnosis for IUGR is done via two methods: Ultrasound tests and Non-stress testing (monitoring of fetal heartbeat).
When the fetus is diagnosed with IUGR, its weight is “less than the 10th percentile” – this means that it weighs 90 percent less than all other fetuses that are of the same gestational age.
Fetal Growth Restriction manifests itself in two ways:
- Symmetric or primary growth restriction occurs when all the internal organs are reduced in size. Usually, this condition accounts for 20% to 25% of all cases of growth restriction.
- Asymmetric or secondary growth restriction is characterized by the head and brain being normal in size. However, the abdomen of the fetus is smaller. The condition is not evident until the third trimester of the pregnancy .
Newborn babies diagnosed with IUGR are usually pale and and have loose, dry skin. The umbilical cord is thinner and dull-looking rather than shiny and fat. However, some babies do not display these physical symptoms, but are physically smaller in size compared to other babies.
Risk Factors For Growth Retardation
Maternal Risk Factors
The following risk factors are related to the mother’s physical profile, lifestyle and medical history :
- Age less than 17 years or greater than 30 years
- Alcohol consumption
- Short in stature
- Low weight
- Low weight gain during pregnancy
- Previous preterm delivery
- Previous abortion 
- Stress and Distress 
- Pollution (exposures to sulfur dioxide (SO2) and total suspended particles (TSP) during the third trimester of pregnancy) 
- Consumption of Fatty Fish (a known route of exposure to persistent organic pollutants) 
- Snoring 
- Consumption of antibiotics
- Kidney disease, advanced diabetes, high blood pressure, heart/respiratory issues and other chronic infections
While caffeine consumption has been perceived as a risk factor, studies seem to indicate that moderate caffeine consumption does not increase IUGR risk .
Some risk factors are external to the fetus but localized in the uterus and placenta:
- Decreased uterine blood flow
- Reduced blood flow in the placenta
- Infections in the tissues surrounding the fetus
- Placenta previa – a condition where the placenta attaches itself quite low to the uterus
While maternal and intrauterine factors originate outside the fetus, some risk factors are intrinsic to the fetus (more likely to lead to symmetric IUGR):
- Multiple Gestation
- Birth/ Genetic defects
- Chromosomal abnormality
- Vertical Infections
What Can IUGR Lead To?
IUGR has been linked to a variety of neurodevelopmental disorders.
- Learning and memory deficiencies 
- An increased risk for schizophrenia was found in boys who were small for their gestational age at birth (odds ratio 3.2) 
- Many human fetuses have to adapt to a limited supply of nutrients. In doing so they permanently change their structure and metabolism. These programmed changes may be the origins of a number of diseases in later life, including coronary heart disease, hypertension, and noninsulin- dependent diabetes. 
- Restricted fetal growth and teenage motherhood were associated with both suicide completion and attempt in offspring. 
- Intrauterine Growth Restriction (IUGR). Stanford Children’s Health.
- Intrauterine Growth Restriction (IUGR); Small For Gestational Age. American Pregnancy Association.
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