Abdominal circumference profiles of macrosomic infants born to mothers with or without hyperglycemia in China.

Objectives: Serial measurements of sonographic fetal abdominal circumference (AC) are useful for monitoring fetal growth during pregnancy and are essential for predicting macrosomia. The study was aiming to compare the AC profiles of infants born to mothers with or without hyperglycemia in Chinese population. Subjects and methods: The "GDM Prevalence Study (GPS)" was a large study conducted in 22 hospitals in three large cities in China, which included 34,085 NGT (normal glucose tolerant) women, 8272 GDM (gestational diabetes mellitus) women and 729 DM (diabetes mellitus) women. A total of 116,740 scans and 103,377 valid AC measurements were performed for the NGT, GDM and DM groups at different gestational age. AC profiles and fetal growth rates at different stages of pregnancy were compared between different groups. Results: The overall AC growth rate (β) was higher in the macrosomia group than in the no macrosomia group in NGT (β =10.250 versus 9.541, p < .001), GDM (β = 10.572 versus 9.705, p < .001) and DM (β = 11.363 versus 9.924, p < .001) pregnancies. Significant differences were observed between NGT-macrosomia, GDM-macrosomia and DM-macrosomia. Significant differences were also noted between NGT-no macrosomia, GDM-no macrosomia and DM-no macrosomia women. Participants in NGT-macrosomia group exhibited larger AC values than NGT-no macrosomia group beginning at 21 gestational weeks, and GDM-macrosomia group exhibited larger AC values than GDM-no macrosomia group beginning at 22 gestational weeks. AC growth rate was higher in NGT-macrosomia and GDM-macrosomia groups than in the corresponding no macrosomia groups between 22 and 30 gestational weeks. Conclusions: The overall AC growth rates are higher in macrosomia group compared to the no macrosomia group in NGT, GDM as well as DM participants. The significant difference of AC growth rates in NGT-macrosomia and GDM-macrosomia indicate the possible differential underlying mechanisms in developing macrosomia with or without hyperglycemia exposure. Our study demonstrate that larger fetal AC measurements around 21-22 weeks are associated with subsequent diagnosis of macrosomia, suggesting that macrosomia management should be initiated much earlier than we thought.