Symphysio-Fundal Height Nomogram In Ultrasound Dated Pregnancies

Objective: Fundal height measurements in centimeters have always been an objective method of evaluating fetal growth in pregnancy. The accepted Mcdonald's rule refers primarily to Caucasians regrettably. Since fundal height may actually vary in an anthropological sense it was considered necessary to apply Mcdonald's rule to African subjects to see whether there is any significant difference. The aim of this study is to construct symphysio-fundal height nomogram for normal pregnant Nigerian women. Material & Methods: In a cross sectional mode, four hundred and five pregnant Nigerian women were studied to examine how their fundal height values compared with those in the literature. A regression equation was derived for the 10th and 90th centiles. Values outside the range of 10 – 90th centiles are to be used for the prediction of small-for-dates and large-for-dates babies respectively. The prediction formulae for the various centiles derived from regression analysis and their usefulness in clinical anthropological practice using fundal height measurement are highlighted. Results: The study demonstrated a significant difference in fundal height values of Nigerian women especially in late pregnancy compared with other published values in the literature. A positive linear correlation between symphysio-fundal height and fetal gestational age was found in Nigerians with a correlation coefficient of R2 = 0.9962 (p<0.001). The relationship is best described by the second order polynomial regression equation y = – 0.0024x2 + 1.1255x – 1.8334 where y is the symphysio-fundal height in centimeters while x is the gestational age in weeks. Conclusion: Symphysio-fundal height chart is a valuable tool for assessing fetal growth in the antenatal clinic in as much as it is cautiously constructed for a given population and the same method of measurement is strictly adhered to by different observers in the same organization.