Management of Macrosomia Associated with Elevated Triglycerides and High BMI in Pregnancy

Risk Assessment and Screening

Early pregnancy screening for pre-existing type 2 diabetes is essential, especially in women with obesity 1

Medical nutrition therapy should be the cornerstone of management, with an individualized nutrition plan developed by a registered dietitian nutritionist familiar with GDM management 2
Physical activity and appropriate weight management should be encouraged to achieve glycemic targets and promote appropriate gestational weight gain 2

Insulin therapy should be considered when dietary measures fail to achieve glycemic targets, particularly in women with early macrosomia (between 29-33 weeks gestation) 3, 2
Metformin and glyburide are not recommended as first-line agents as they cross the placenta, but may be considered when insulin is not an option 2
For women with a BMI ≥35.0 kg/m², low-dose aspirin (75-180 mg daily) from 12 weeks until delivery may be considered to reduce the risk of preeclampsia 1

Self-monitoring of blood glucose is essential, targeting fasting glucose <95 mg/dL, one-hour postprandial glucose <140 mg/dL, and two-hour postprandial glucose <120 mg/dL 2
Ultrasound assessment should include early anatomy scan between 14-16 weeks gestation 1
Ultrasound assessment should include routine morphology scan at 20-22 weeks gestation 1
Regular growth scans starting in the second trimester and repeated every 2-4 weeks to monitor for macrosomia 2
Mothers should be taught to monitor fetal movements during the last 8-10 weeks of pregnancy 4, 2

The risk of cesarean delivery at least doubles when fetal weight is estimated to be more than 4,500g 3
Current evidence does not support early induction of labor for suspected fetal macrosomia, as it may double the risk of cesarean delivery without reducing the risk of shoulder dystocia 3
Prophylactic cesarean delivery should be considered for estimated fetal weights of ≥5,000g 3
In the absence of other obstetric or medical indications, obesity alone is not an indication for induction of labor 1

Shoulder dystocia risk increases to 9.2-24% when birth weight exceeds 4,500g in non-diabetic pregnancies and 19.9-50% in pregnancies complicated by diabetes 3
Early establishment of venous access during labor is recommended in women with a BMI above 40 1
Active management of the third stage of labor is recommended for all women with a BMI ≥30 due to increased risk of postpartum hemorrhage 1
Antenatal thromboprophylaxis should be considered, especially before cesarean section or when hospitalized prior to delivery 1

Women with GDM should be tested for persistent diabetes or prediabetes at 4-12 weeks postpartum with a 75-g oral glucose tolerance test 2
Continued testing every 1-3 years is recommended due to the 50-70% lifetime risk of developing type 2 diabetes 2
Breastfeeding should be encouraged as it may reduce obesity in children and provide metabolic benefits to both mother and offspring 2
Postpartum weight loss should be encouraged for women who were overweight or obese during pregnancy 2

LGA is defined as birth weight above the 90th percentile for gestational age (adjusted for sex), whereas macrosomia is defined by absolute birth‑weight cut‑offs; > 4 000 g is the traditional definition, and > 4 500 g marks a clinically significant threshold where complication rates rise sharply. 5

Shoulder dystocia occurs in 19.9 %–50 % of deliveries when the infant’s birth weight exceeds 4 500 g in diabetic pregnancies, compared with 9.2 %–24 % in non‑diabetic pregnancies. 5
Undiagnosed or untreated gestational diabetes mellitus confers up to a 20 % risk of delivering a macrosomic infant. 5

Gestational age beyond 40 weeks is associated with a progressive increase in the risk of macrosomia. 5

For pregnancies complicated by diabetes, an estimated fetal weight (EFW) > 4 500 g strongly warrants consideration of cesarean delivery. 5
Cesarean delivery risk at least doubles when the EFW exceeds 4 500 g, regardless of diabetes status. 5

Shoulder dystocia is observed in approximately 1.4 % of all vaginal deliveries but rises to 9.2 %–24 % when birth weight exceeds 4 500 g in non‑diabetic pregnancies. 5
Brachial‑plexus injury risk increases 18‑ to 21‑fold in infants weighing > 4 500 g. 5
Clavicular fracture risk increases about 10‑fold in infants > 4 500 g. 5