Fetal Biometry in the Population of Southern Punjab, Pakistan

Ultrasound estimation of fetal parameters is one of the most important examinations. Hadlock and other foreign fetal biometry curves are used in Pakistan as there are no national normative data derived from local population. To construct local reference charts and equations for fetal biometric measurements and amniotic fluid index (AFI) using a large sample of fetuses examined at 14 - 40 weeks in the population of southern Punjab. The prospective, cross sectional study conducted at the Multan Institute of Nuclear Medicine and Radiotherapy (MINAR) over a one year period from December 2010 to November 2011. A total of 566 randomly selected pregnant females, who fulfilled the inclusion criteria were included in the study after informed consent. Each woman was scanned once only, between 14 and 40 weeks of gestation, and her fetal measurements were also recorded simultaneously. Regression models were used to estimate the mean and standard deviation at each week of gestation. Fetal biometric parameters of local population were compared with those of Hadlock and Singaporean Asian population. Results were statistically analyzed and also presented graphically across the different gestational ages to allow visual comparison. Biometric measurements were obtained for 566 fetuses. There was no significant difference between fetal parameters of local population and those of Hadlock. When compared with those of the Singaporean Asian population, femur length and head circumference were larger while biparietal diameter was smaller in our population. We have constructed local reference centiles for fetal measurements and equations for dating of pregnancy for Southern Punjab. The biometric measurements are slightly different from Singaporean Asian population, but there was no statistically significant difference between these measurements and those by Hadlock.