1. Intrauterine growth retardation
(IUGR)
By: Fikadu T.
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2. Course objectives
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At the end of this lesson the student will be able
to:-
• Define IUGR
• Describe causes of IUGR
• Describe IUGR diagnosis methods
• Propose prevention and management options

3. IUGR
• A condition in which a fetus is unable to achieve its
genetically determined potential size.
• Infants <10th percentile are classified as having intrauterine
growth restriction (IUGR)
• Infants >90th percentile are classified as large for
gestational age (LGA) as determined by ultrasound.
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8. Physiology of growth
• Fetal growth is dependent on genetic, placental, and
maternal factors
• Growth is determined by substrate availability and the
integrity of physiologic processes.
• Key physiologic mechanisms required for optimal fetal growth
are.
 Expansion of maternal plasma volume,
 Maintenance of uterine blood flow,
 Development of adequate placentation
 Insulin-like growth factors (IGFs) are important mediators of
substrate incorporation into fetal tissue
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9. Physiology of growth
Phases of normal cellular growth
• Three consecutive dynamic cell growth phases
1.Cellular hyperplasia:- occurs during the 1st 16 wks of
gestation, 5 g/day growth rate at 15wks.
2. Hyperplasia & hypertrophy:- extends up to 32 wks, 24g/day
growth rate at 24wks. Occurs in mid gestation
3. Hypertrophy:- after 32wks, most fetal fat and glycogen
deposition takes place, 30g/day growth rate at 34 wks
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10. Etiology
• Any known & unknown condition w/h
persistently interferes with fetal oxygenation and
nutrition causes IUGR
• Intrinsic, extrinsic and combination influences
both
•
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14. Weight gain during pregnancy
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 Six kg of the average 11 kg weight gain is composed of
maternal tissues
 Uterus—0.9 kg
 Breasts—0.4 kg
 Increase in blood volume—1.3 kg
 Increase in extracellular fluid—1.2 kg
 Accumulation of fat (mainly) and protein—3.5 kg
 Of 5 kg of fetal tissues
 Fetus—3.3 kg,
 placenta—0.6 kg and
 liquor—0.8 kg foetus)
 Of this 11 kg, 7 kg are water, 3 kg fat and 1 kg protein

15. Water retention
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• During pregnancy, the amount of water retained at
term is about 6.5 litters
• Maternal blood volume: 1500–1600 mL
 Plasma volume: 1200–1300 mL
 Red cell volume: 300–400 mL
Uterus and breasts
 Extracellular fluid, Intracellular fluid and adipose
tissue 1500 –2500 ml
• Fetus, placenta and amniotic fluid- 3500ml

16. Extrinsic factors of IUGR
Maternal lifestyle
Infections in the mother
Exposure to certain drugs(anticonvulsants,
methotrexate) or X-rays
Cardio-vascular disease: preeclampsia, hypertension,
cardiac disease
Malnutrition or anemia in the mother
The disease of placenta like malaria
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17. Intrinsic factors of IUGR
• Intrinsic fetal causes of poor growth include
• Chromosomal abnormalities (in particular
aneuploidy)
• Congenital infection (TORCH)
• A birth defect like cardiovascular, renal,
anencephaly, limb defect, etc.
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18. Placental or Umbilical cord causes of IUGR
 Inadequate development or maintenance of placenta
results in inadequate blood flow to placenta
 Due to placenta previa, placenta abruption, placental
infarction, placenta accreta…
 Impaired umbilical cord exchange
 Chorioangioma, twin-twin transfusion syndrome (TTS)
 Infections
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19. Classification of IUGR
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20. Diagnosis
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• Can be difficult to diagnose until the baby is
born.
A. Clinical:
SFH, Fetal mass
Maternal weight gain- stationary or decreasing
Abdominal girth- stationary or decreasing

21. IUGR
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Ultrasound parameters to diagnose IUGR include:
i. HC/AC ratio: Normally before 32 weeks is >1, at 32-
34 weeks is =1 and after 34 weeks is <1
Asymmetric
– IUGR, head remains larger and the ratio is elevated
Symmetric
– both the HC and AC are reduced
– IUGR, the ratio is normal
• HC/AC diagnose 85% of IUGR

23. IUGR
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FL/AC: is 22 at all gestational ages from 22weeks to term.
• Femur length is unaffected in asymmetric IUGR.
• FL/AC ratio >23.5 is suggestive of IUGR
iii. Amniotic fluid volume: reduced amniotic fluid is
associated with asymmetric IUGR
 Single deepest vertical pocket (SDVP) of amniotic fluid < 1 cm
suggests IUGR in 96% of fetuses
 NOTE: AC is the single most sensitive parameter to detect IUGR
iii. B/L ratio of >5;1

24. Diagnose
• The gold standard to diagnose IUGR is Doppler U/s
• During normal pregnancy, there is an increase in placenta
size and blood flow volume, resulting in a decrease in
resistance (impedance to maternal blood flow, leading to
low blood resistance
• Suboptimal placental growth and function, generally
referred to as placental insufficiency, is the common cause
of fetal growth restriction
• The more sever placental insufficiency the worst the fetal
consequence

25. Diagnose
• With placental insufficiency, placental impedance
is higher than normal and results in diastolic
abnormalities such as decreased, absent or reversed
end diastolic flow in fetal vessels

28. Management
• At present, there is no proven therapy for reversing IUGR
once it established
• However, early diagnosis and treatment of the underlying
problem may reduce the chance of serious outcome.
 Adequate bed rest
 Correct malnutrition
 Appropriate therapy for the associated complicating factors
 Avoidance of smoking, tobacco and alcohol
 Maternal hyper oxygenation
 Low dose aspirin (50 mg daily) for selected cases
 Maternal volume expansion

29. Judge Optimum Time Of Delivery
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Risk of prematurity
Difficult extra uterine
existence
Risk of IUFD
Hostile intra uterine
environment

30. • Optimum time of delivery
A. Pregnancy ≥ 37 weeks: Delivery should be
done
B. Pregnancy < 37 weeks with Uncomplicated
mild IUGR:
– conservative Rx to improve the placental
function
– Pregnancy is continued at least 37 weeks and
thereafter delivery is done

31. C. Severe degree of IUGR:
• Delivery should be planned on the basis of fetal
surveillance report
• If the lung maturation is achieved delivery is done
• If the lung maturation has not yet been achieved,
antenatal corticosteroids should be given
• Delivery to be done at 34 0/7 weeks of gestation in
cases of FGR with additional risk factors
• Magnesium sulfate if before 32 weeks.
– MgSO4 IV 20% 4 gm over 10–15 minutes, followed by IM
5 gm every 4 hours for 24hours

32. Treatment cont...
Fetal surveillance
• Fetal kick counts,
• Non-stress test,
• Amniotic Fluid Index,
• Doppler of the Umbilical Artery &
• Biophysical Profile
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33. Mode of delivery
• C/S– to be done in the case of preterm
delivery, presence of fetal acidemia, absent
or reversed diastolic flow in umbilical artery
or unfavourable cervix
• Baby should be shifted to intensive neonatal
care unit (NICU)

34. Complications
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35. Prevention
• Cessation of smoking
• Protein and energy supplementation
• Anti-malarial chemoprophylaxis
• Screening for CMV, HSV, Rubella, toxoplasmosis
• Avoid drugs
• Control maternal chronic illnesses
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