Introduction: Gestational diabetes (GD) is associated with a significantly higher risk of perinatal complications. It has been suggested that third-trimester (3thT) foetal abdominal circumference (fAC) determination is an important predictor of macrossomia and large for gestational age (LGA).
Aims: The purpose of this study was to evaluate the association between the 3thT fAC percentile with birthweight (BW) and adverse neonatal outcomes in a cohort of women with GD.
Methods: We retrospectively analysed the fAC percentile of the 3thT ultrasound screening in pregnant women with GD within a 2 years period in a Central University Hospital. We enrolled 268 pregnant women with singleton pregnancy undergoing routine fetal biometry after 28 weeks. The relationship between fAC and BW was explored using the Spearmans correlation and among fAC percentile groups (<50; ≥50) and adverse neonatal outcomes using the Fishers exact test.
Results: The study included 268 singleton pregnancies; the median maternal age was 33 years old (range, 1752) with a median delivery week of 39 weeks (range, 2941). The median BW was 3165 g (range, 13704450), 3thT ultrasound gestational age measurement 36 weeks (range, 2940) and fAC percentile 50 (range, 1100). Neonatal outcomes prevalences: neonatal morbidity compositum (n=67; 25%), small for gestational age (n=25; 9.3%), LGA (n=24; 9.0%), macrossomia (n=12; 4.5%), and neonatal hypoglycaemia (n=5; 1.9%). The macrossomia and LGA rates were greater in the fAC percentile group ≥50 compared to <50 (91.7% vs 8.3% and 95.8 vs 4.2% respectively) (P<0.05). There was no significant difference in neonatal hypoglycaemia rate between groups (80% vs 20%, P=0.384). We documented a strong positive correlation between fAC and BW: R=+0.626, P<0.001 (R2=0.392).
Conclusions: The intrapartum fAC measurement was useful in screening fetal macrossomia and LGA. These results suggest that fAC measured by ultrasound can help to predict the BW and seems to be a valuable parameter to be included when we evaluate a gestational diabetic pregnant woman.