A longitudinal study of fetal growth using antenatal INTERGROWTH-21ST reference standard charts and perinatal outcome

• Author Details:   
• Akshitha K
• Roopa M
• Sneha G. S
• Sahana N Naik
• Rathnamala M Desai
• Udayashree Voorkara ^*

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Background: Neonatal growth charts reveal compromised growth only at the extreme of growth abnormalities. They cannot be used to identify the fetus whose birth-weight is above the 10th percentile but has failed to achieve its growth potential. Hence we performed a longitudinal study of antenatal fetal growth assessment using INTERGROWTH-21st (IG-21st) reference standard charts and correlated with neonatal outcome.

Aim & Objectives: To assess the predictive value of antenatal fetal INTERGROWTH-21st (IG-21st) reference standard charts in diagnosing the neonatal growth abnormalities and the perinatal outcome

Materials and Methods: A prospective longitudinal study was done on 100 patients visiting outpatient department (OPD) of Department of OBG, SDMCMSH, Dharwad, Karnataka, for regular ante natal care (ANC), booked at <14 weeks of gestation.

Serial ultrasounds (USG) were done, i.e. Dating Scan, nuchal translucency scan (NT scan), Anomaly Scan, Growth Scan at >32weeks and one at near term. Fetal biometry measured (CRL-crown rump length, BPD-Biparietal diameter, HC-head circumference, AC-abdominal circumference, FL-femoral length, EFW-estimated fetal weight) were plotted on IG-21st charts and monitored the fetal growth. The neonatal parameters at birth and perinatal outcome were noted.

Results: Ninety six (96%) fetuses had normal growth curves (NGC) for all assessed parameters. Four (4%) had growth curves (GC) for AC and EFW falling below NGC indicating fetal growth restriction (FGR).At birth, all these 4 babies (100%) had LBW indicating that fetal monitoring using IG-21st had accurately identified all (100%) fetuses at risk for FGR and AC and EFW were better parameters for assessment of FGR compared to HC, BPD and FL.), but were AGA (appropriate for gestational age); thus, indicating applicability of IG-21st.

Conclusion: The IG-21st reference standards have a high predictive value for growth deviations and applicable to our population for antenatal fetal growth monitoring.