A Relationship between Gestational Age Determined by Ultrasound Biometric and Symphysis Fundal Height Measurements

Abstract

Last Menstrual Period (LMP), Symphysis fundal height (SFH) or Ultrasound biometric measurements are being used to determine the gestational age (GA) and expected delivery date (EDD) by various ante-natal care (ANC) providers for pregnant women in both urban and rural areas. However, each method has its limitations in determining accurate gestational age of the fetus at different stages of gestation. Ultrasound facilities may not be readily available in some rural setups or may not be affordable for some pregnant women. Many have to depend on SFH measurements as actual LMP may not be remembered by the women when they visit ante-natal clinics. This study aims to establish a relationship between gestational age estimated by ultrasound biometric measurements and fundal height measurements to compute accurate gestational ages by measurement of fundal heights using 100 pregnant women. A non-linear regression equation was fitted from the measured data.  The relationship between the gestational age(wks) and the fundal height(cm) was obtained from the mathematical modeling of the data by the equation GESTATIONAL AGE(wks) = 9.166 e ^{0.039 (FUNDAL HEIGHT)(cm)} with R² = 0.931.

Keywords: Gestational Age, Last menstrual age, Symphysis-fundal height, Ultrasound