Makindo Medical Notes

LGA infants are those with a birth weight above the 90th percentile for gestational age. Most are due to maternal diabetes or obesity. Anticipating delivery complications and metabolic instability is key. 👶

🧬 Causes

• Maternal diabetes (gestational or pre-existing) 🍭
• Maternal obesity (↑ nutrient supply)
• Post-term pregnancy (>42 weeks)
• Genetic predisposition (large parents)
• Excessive gestational weight gain
• Rare endocrine syndromes (e.g., Beckwith-Wiedemann)

⚠️ Risks

• Shoulder dystocia during labour 🚨
• Operative or cesarean delivery
• Birth trauma (brachial plexus palsy, clavicle fracture)
• Neonatal hypoglycemia (fetal hyperinsulinism)
• Respiratory distress syndrome (if preterm + C-section)
• Later obesity & T2DM 📈

🧪 Investigations

• Ultrasound for estimated fetal weight (EFW)
• Maternal glucose tolerance testing
• Amniotic fluid assessment (polyhydramnios common)

🩺 Management

• Screen and control maternal diabetes
• Plan delivery route if macrosomia suspected (>4.5 kg → elective C-section)
• Careful intrapartum monitoring for shoulder dystocia
• Neonatal: frequent glucose monitoring
• Long-term: growth trajectory, obesity prevention, diabetes risk follow-up

💡 Pearls: - LGA babies of diabetic mothers often have organomegaly (large liver, heart) due to insulin effect. - Plan mode of delivery early if macrosomia suspected. - Vigilant neonatal monitoring for hypoglycemia is essential.

🧑‍⚕️ Case Examples — Large-for-Gestational-Age (LGA) Infants

• Case 1 (Diabetic mother): 🍭 A 30-year-old woman with poorly controlled gestational diabetes delivers a baby at 39 weeks by elective C-section. Birth weight is 4.8 kg (>97th centile). The neonate is initially well but develops jitteriness and hypoglycemia within 2 hours. Diagnosis: LGA infant of a diabetic mother with neonatal hypoglycemia. Managed with early feeding and IV dextrose. Discharged after stabilisation with advice for long-term obesity and diabetes risk monitoring.
• Case 2 (Shoulder dystocia): 🚨 A 36-year-old multiparous woman with BMI 34 undergoes induced labour at 41 weeks. The baby weighs 4.7 kg. Delivery is complicated by shoulder dystocia, requiring McRoberts’ manoeuvre and suprapubic pressure. The neonate sustains a transient Erb’s palsy but recovers with physiotherapy. Diagnosis: Birth trauma from LGA due to maternal obesity and post-term pregnancy.
• Case 3 (Syndromic LGA): 🧬 A term male infant is born weighing 4.6 kg to non-obese, non-diabetic parents. Exam shows macroglossia, abdominal wall defect, and neonatal hypoglycemia. Genetic testing confirms Beckwith-Wiedemann syndrome. Diagnosis: Syndromic LGA with metabolic instability. Managed with IV glucose, tumour surveillance protocol (risk of Wilms tumour/hepatoblastoma), and multidisciplinary follow-up.