Variation of Fetal Biometry with Maternal Ethnicity: A Cross-Sectional Study in Accra

Abstract

Background: Variable fetal biometric values are common in normal fetuses and it is natural to assume that ethnicity might influence this. There is the potential danger of misinterpretation of such observed normal variations. Aims: The study aim was to determine whether differences in ultrasound-measured fetal biometry exist among pregnant women of the Akan, Mole-Dagbon, Ewe and Ga-Adangbe ethnic groups in Accra. Methods: This was a prospective cross-sectional study involving 448 women with uncomplicated singleton pregnancies, certain date of the last menstrual period and presenting between 19weeks and 28weeks of gestation. The participants were selected by proportional quota sampling and comprised 148 Akans, 119 Mole-Dagbon, 96 Ewes and 85 Ga-Adangbes. Each woman was scanned by transabdominal ultrasound once for the study. The biparietal diameter, head circumference and femur length were measured. These were compared by Krukal Wallis test for any significant variations among the four ethnic groups. Maternal age, height and parity were also analysed for any association with the fetal biometric variations. Results: There were significant variations in femur length measurements (p<0.05) among the four ethnic groups. There were no statistically significant variations in the biparietal diameter (p>0.05) and head circumference (p >0.05) measurements. There was no association between maternal characteristics and variations observed in the femur lengths measurements. Conclusion: The findings suggest that maternal ethnicity influence foetal femur length measurements in second trimester foetuses. However, a further study with a larger sample size selected across the country is recommended to ascertain if the observed fetal biometric variations has a national character.