Large for Dates pregnancy Flashcards
Define
Term to identify macrosomic babies (≥4kg or ≥4.5kg – the definition varies) -> 10% of pregnancies
· Prenatally, 3 tools used to diagnose large for age
o 1st -> Symphysis-fundal height (SFH) à >90th/95th centile for gestational age à foetal biometry…
o 2nd -> Abdominal Circumference (AC) à >90th/95th centile for gestational age
o 2nd -> Estimated foetal weight (EFW) à >90th/95th centile for gestational age
Risk factors
- High BMI
- Foetal macrosomia (>4kg in a term infant)
- Gestational or DM
- Syndromes: Beckwith-Wiedemann, Simpson-Golabi-Behemel, Soto’s syndrome
- Molar pregnancy
- Polyhydramnios
- Multiparity
- Advanced maternal age
Signs and symptoms
On inspection -> excessive distension for gestational age
Abdomen -> increased SFH (symphysis fundal height), increased abdominal circumference
Investigation
OGTT – for gestational diabetes
Bloods – serum βHCG
USS – liquor volume, biometry
Genetic testing
Management
Detected at 18-21 weeks à repeat scan
Detected at 24-36 weeks à if acceleration of growth, arrange USS for foetal biometry
- If follows same path (no drop/rise growth), then reassure this is normal, arrange another routine scan
- Offer OGTT (gestational diabetes)
Detected at 36-40 weeks à if SFH is >90th centile on routine measurements à USS for foetal biometry
- If EFW and AC on USS are >95th centile, return to routine care
- Perform OGTT (gestational diabetes)
- Care in labour + postnatally as per gestational diabetes dx at earlier gestation
Need to plan delivery and discuss risk of shoulder dystocia, nerve injuries, prolonged labour à offer CS
Complications
- Shoulder dystocia
- Hypoglycaemia in GDM
- Respiratory distress syndrome – combination of GDM, need to deliver earlier
- Intrauterine deformations – metatarsus adductus (foot bends inwards), hip subluxation
- Increased mortality
- Perineal tear
- Prognosis -> early planning/care -> no difference in outcomes for LGA compared to normal
