ESTIMATION OF BIRTH WEIGHT BY MEASURING THE FUNDAL HEIGHT AND ABDOMINAL GIRTH_IN PARTURIENTS ADMITTED TO MOBINI HOSPITAL IN SABZEVAR, IRAN

Background and The diagnosis of women with LBW or macrosomic infants through a simple convenient means provides them with timely and appropriate caregiving. In this study, the value of symphysis-fundal height and abdominal girth in predicting birth weight was examined. Methods and Materials: In this descriptive cross-sectional study, the study population included parturients of 38-42 weeks gestational age. 795 parturients admitted to Shahidan Mobini hospital in Sabzevar, Iran were purposively selected. The inclusion criteria were bearing single alive term fetus and longitudinal lie. Women with severe fetal anomaly, presence of thick fat layer at the lower abdomen, oligohydramnios or polyhyramnios based on ultrasound reports were excluded. Symphysis-fundal height and abdominal girth were measured a few hours before delivery and birth weight was measured after delivery. Birth weight was predicted by using two formulae: (Birth weight = fundal height * abdominal girth) and (Regression model of birth weight over fundal height). Relevant data were analyzed using correlation coefficient, regression, covariance analysis and t-test in SPSS. 56% of the sample were primipara. Head engagement occurred only in 21.9% before admission to the hospital. The correlation between birth weight and fundal height measurement was 0.581 (p = 0.000). The correlation between birth weight and fundal height multiplied by abdominal girth measurement was 0.56 (p = 0.000). To predict birth weights more than 4000 grams, the sensitivity and specificity of fundal height multiplied by abdominal girth measurement with cut point 3900 gram were 81% and 82% respectively. For the second formula with cut point 3450 gram, these figures were 75% and 85% respectively. To predict birth weights less than 2500 grams, the sensitivity and specificity of fundal height multiplied by abdominal girth measurement with cut point 3000 gram were 70% and 79% respectively; for the second formula with the same cut point, these figures were 77% and 85% respectively. In order to detect infants with birth weights more than 4000 grams, the first formula with cut point 3900 gram is more valid and better than the second formula but for the prediction of birth weights less than 2500 grams, the second formula, with cut point 3000 gram, is more valid than the first.