FETAL COMPLICATIONS
Table of Contents
IUGR (Fetal Growth Restriction) .................................................................................................... 2
FETAL MALPOSITION ...................................................................................................................... 7
FETAL MALPRESENTATION ........................................................................................................... 11
External Cephalic Version (ECV) ................................................................................................... 15
HYDROPS FETALIS ......................................................................................................................... 18
Intrauterine Fetal Demise (IUFD) ................................................................................................. 22
1
,IUGR (Fetal Growth Restriction)
Definition • Fetus that fails to achieve its genetically predetermined growth
potential.
• Often operationally defined as:
o Estimated fetal weight (EFW) < 10th percentile
• Severe IUGR: EFW < 3rd percentile
Exam Trap: Not all small babies are IUGR → distinguish from SGA (Small
for Gestational Age)
Classification A. Based on Pattern
1. Symmetrical IUGR
• Proportionately small (head & body)
• Early insult
2. Asymmetrical IUGR (more common)
• Head sparing (normal HC, small AC)
• Late pregnancy insult
B. Based on Onset
Type Timing Cause
Early-onset <32 weeks Placental
insufficiency,
chromosomal
Late-onset ≥32 weeks Uteroplacental
insufficiency
Etiology & Risk Maternal
Factors • Hypertension / Pre-eclampsia
• Diabetes (vascular disease)
• Smoking, alcohol
• Malnutrition
• Chronic diseases (renal, SLE)
Fetal
• Chromosomal abnormalities (e.g. Trisomy 21)
• Congenital infections (TORCH)
• Multiple pregnancy
Placental (MOST IMPORTANT)
• Placental insufficiency
• Abruption
2
, • Abnormal cord insertion
Viva Point: Placental insufficiency is the commonest cause overall
Pathophysiology • Poor placental perfusion → ↓ oxygen & nutrients
• Fetal adaptation:
o Blood shunted to brain, heart, adrenals
o ↓ perfusion to liver → ↓ glycogen → ↓ abdominal size
Leads to:
• Head sparing (asymmetrical IUGR)
• Oligohydramnios (↓ renal perfusion)
Clinical Features Symptoms
• Often asymptomatic
• Mother may notice ↓ fetal movements
Signs
• SFH < gestational age
• Poor maternal weight gain
*Always compare serial measurements, not single reading
Clinical Pearl • Previous IUGR = consider current high-risk pregnancy
• Often diagnosed late in 3rd trimester after serial assessment of
Growth parameter (at least 3x taken ≥2 weeks apart)
➢ Growth parameters monitored only during 3rd trimester
• Once diagnosed, require delivery
Incidence • 85% SGA are constitutionally small
• 15% SGA are truly IUGR
3
Table of Contents
IUGR (Fetal Growth Restriction) .................................................................................................... 2
FETAL MALPOSITION ...................................................................................................................... 7
FETAL MALPRESENTATION ........................................................................................................... 11
External Cephalic Version (ECV) ................................................................................................... 15
HYDROPS FETALIS ......................................................................................................................... 18
Intrauterine Fetal Demise (IUFD) ................................................................................................. 22
1
,IUGR (Fetal Growth Restriction)
Definition • Fetus that fails to achieve its genetically predetermined growth
potential.
• Often operationally defined as:
o Estimated fetal weight (EFW) < 10th percentile
• Severe IUGR: EFW < 3rd percentile
Exam Trap: Not all small babies are IUGR → distinguish from SGA (Small
for Gestational Age)
Classification A. Based on Pattern
1. Symmetrical IUGR
• Proportionately small (head & body)
• Early insult
2. Asymmetrical IUGR (more common)
• Head sparing (normal HC, small AC)
• Late pregnancy insult
B. Based on Onset
Type Timing Cause
Early-onset <32 weeks Placental
insufficiency,
chromosomal
Late-onset ≥32 weeks Uteroplacental
insufficiency
Etiology & Risk Maternal
Factors • Hypertension / Pre-eclampsia
• Diabetes (vascular disease)
• Smoking, alcohol
• Malnutrition
• Chronic diseases (renal, SLE)
Fetal
• Chromosomal abnormalities (e.g. Trisomy 21)
• Congenital infections (TORCH)
• Multiple pregnancy
Placental (MOST IMPORTANT)
• Placental insufficiency
• Abruption
2
, • Abnormal cord insertion
Viva Point: Placental insufficiency is the commonest cause overall
Pathophysiology • Poor placental perfusion → ↓ oxygen & nutrients
• Fetal adaptation:
o Blood shunted to brain, heart, adrenals
o ↓ perfusion to liver → ↓ glycogen → ↓ abdominal size
Leads to:
• Head sparing (asymmetrical IUGR)
• Oligohydramnios (↓ renal perfusion)
Clinical Features Symptoms
• Often asymptomatic
• Mother may notice ↓ fetal movements
Signs
• SFH < gestational age
• Poor maternal weight gain
*Always compare serial measurements, not single reading
Clinical Pearl • Previous IUGR = consider current high-risk pregnancy
• Often diagnosed late in 3rd trimester after serial assessment of
Growth parameter (at least 3x taken ≥2 weeks apart)
➢ Growth parameters monitored only during 3rd trimester
• Once diagnosed, require delivery
Incidence • 85% SGA are constitutionally small
• 15% SGA are truly IUGR
3
