LGA

Question 1

What is LGA?

Answer 1

large for gestational age
birth weight >4,500g
Macrosomia

Question 2

What are the causes of LGA?

Answer 2

Diabetes
post term pregnancy
maternal obesity/ excess weight gain
previous macrosomic infant
genetic presiposition

Question 3

How is LGA detected?

Answer 3

serial clinical examination of SFH
ultrasound EFW or AC > 90th centile.

Question 4

What are the complications of LGA?

Answer 4

1. prolonged labour
2. increased risk of c-section delivery
3. increased risk of vacuum or forceps delivery
4. shoulder dystocia

Question 5

How do you manage LGA?

Answer 5

controversial…

• Screen for gestational diabetes
• Minimize maternal and fetal trauma at delivery

No evidence for:
* Induce by 39 weeks
* Elective CS
* Non-diabeticmotherif>5kg * Diabeticmotherif>4.5kg

Question 6

What are you worried about most with LGA?

Answer 6

Shoulder dystocia

• But, 50% shoulder dystocia occur in normal weight fetus
  
  • Shoulder dystocia impossible to predict or prevent

Turtle sign – head delivers, and then failure of delivery of shoulders – anterior shoulder “stuck” behind pubis
If inappropriate downward traction applied to release anterior shoulder, this stretches brachial plexus, leading to Erb’s palsy (avulsion C5-C6 nerve roots)
Most cases transient, 10% lead to permanent injury – “Waiter’s Tip” position