Intrauterine Growth Restriction (IUGR): Types, Causes and Treatment

Intrauterine growth restriction is defined as if the baby presents with the clinical features of malnutrition or undernutrition like the presence of three or more loose skin folds in the buttock region. The baby will have an emaciated appearance and the peeling of the skin will be found. Along with the clinical features the birth weight of the baby will be between 10^th – 25^th percentile of expected gestational age.

Causes Of Intrauterine Growth Restriction

Maternal Causes Of Intrauterine Growth Restriction

• Underweight mother
• Chronic kidney disease or glomerulonephritis
• Autoimmune disease
• Thrombotic disease
• Hypertensive disorders- Preeclampsia leads to vasospasm which results in less nourishment to the fetus.
  • Smoking and alcohol
  • Togen exposure
  • Uterine anomalies
  • Anemia
  • Radiation exposure

Placental Causes Of Intrauterine Growth Restriction

• Placental malformation
• Placental infarction
• Abruptio placenta
• Placenta previa

Fetal Causes Of Intrauterine Growth Restriction

• Chromosomal anomalies like trisomy 13, trisomy 16.
• Congenital infections like rubella, syphilis, and CMV.
• Constitutional or familial disorders
• Inborn errors of metabolism, like homocystinuria, alkaptonuria, and maple syrup urine disease.
• Multiple gestations

Also Read: BRONCHIAL ASTHMA (Types, Clinical Features & Treatment)

Intrauterine Growth Restriction Types

Symmetrical Intrauterine Growth Restriction

It is early onset growth restriction and it is due to:

• Chromosomal defects
• Congenital anomalies
• Infections like rubella, and CMV.
• The PONDERAL index is normally 8.3. This value is unaffected in symmetrical intrauterine growth restriction. The fetal weight (FW) and fetal length (FL) are reduced.
• Head circumference: Arm circumference ratio ( HC: AC) is maintained at 1 because both of these are compromised.
• In the case of symmetrical intrauterine growth restriction, the prognosis is poor.

Asymmetrical Intrauterine Growth Restriction

• It is late in onset and it is due to hypertension after 20 weeks of gestation which is pregnancy-induced hypertension.
• It is also due to renal diseases like glomerulonephritis or chronic kidney disease.
• The PONDERAL index is less than 7 that is firstly the weight will be reduced and then the femoral length is spared for some time.
• Head circumference: Arm circumference ratio is more than one and it has a sparing effect on the brain therefore the head circumference is maintained.
• The prognosis of asymmetrical intrauterine growth restriction is better.

Also Read: Carbohydrate and Amino Acid Metabolism Disorders

Diagnosis Of Intrauterine Growth Restriction

• If Symphyseal Fundal Height (SFH) lags by >=3cm or 3-4 weeks it indicates a fetal growth restriction.
• Gestational age corresponds to the Symphysis fundal height (SFH).
• This Symphyseal fundal height is measured using a tape from 20 to 34 weeks and it can be compared with gestational age.
• For instance, if a patient’s pregnancy is 32 weeks but the SFH is lagging at 28 weeks it indicates intrauterine growth restriction.
• In Intrauterine growth restriction, the expected Fetal weight is less than the 10^th percentile of Gestational age. This is the most specific criterion.
• The most sensitive criterion is the measuring of arm circumference. Arm circumference less than the 10^th percentile for gestational age is a diagnostic feature of intrauterine growth restriction. It is the first parameter to be affected in fetal growth restriction.

Also Read: Assessment of Growth and Growth Charts by WHO

Complications Due To Intrauterine Growth Restriction

Antepartum

• Oligohydramnios
• Hypoxia
• Stillbirths

Intrapartum

• Hypoxia
• Acidosis

Newborn

• Hypoglycemia due to decreased glycogen stores.
• Hypothermia due to decreased subcutaneous fat.
• Meconium aspiration syndrome
• Hypocalcemia
• Hypoxia and acidosis.
• Increase in erythropoiesis that leads to polycythemia and hyperviscosity syndrome.
• Hyperbilirubinemia

Neonatal Complications

• Limp and loose-skinned
• Respiratory distress syndrome
• Thin fetus with poor tone
• Interventricular hemorrhage
• Neonatal death

Also Read: Neonatal Sepsis: Risk Factors, Clinical Features, Diagnosis & Treatment

Management Of Intrauterine Growth Restriction

• Increase the diet - An adequate diet should be recommended to the malnourished woman. The diet should consist of protein powders, supplements, and fruits.
• On diagnosis, the main target should be to reduce further insult by advising the patient to stop smoking and drinking or any recreational drugs.
• Rule out the wrong dates.
• The mother should be advised to rest in the left or right lateral position because it increases the placental perfusion.
• Regular fetal surveillance should be done with NST and BPP.
• If fetal surveillance parameters are not favorable at less than 37 weeks gestation, then give steroids and try to deliver the baby.
• If the gestation period is less than 34 weeks give steroids to the mother and do fetal surveillance. If the fetal surveillance is not good then delivery should be done.
• If the gestation period is more than 37 weeks and intrauterine growth restriction is detected in the baby then the only management is delivery.

Also Read: Important Hematological Disorders In Children

Prevention Of Intrauterine Growth Restriction

• Balanced energy and protein supplementation should be done as it is found to reduce the risk of intrauterine growth restriction.
• Antioxidants like vitamin C and vitamin E are not found to reduce the risk of intrauterine growth restriction.
• Reduction of caffeine intake is found to be associated with a reduction in risk of intrauterine growth restriction.

Also Read: Nutrition And Malnutrition

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