stuDy oF accuracy oF commonly useDFetal Parameters For estimation oF gestational age (original) (raw)
Related papers
Accuracy of fetal measurements in estimation of gestational age
Innovative Publication, 2016
Back ground: Gestational age (GA) is a fundamental requisite at autopsy as well as for clinical assessment of growth of the fetus within the womb. Fetal parameters like anthropometric measurements and visceral developments can be used for calculation of GA. The present study was conducted with an aim of assessing the accuracy of fetal measurements like Foot length, Head Circumference, Crown-Rump length, Crown-Heel length and Abdominal Circumference for calculation of GA and to derive regression formulas for the same. Methods: The study was conducted on 60 foetuses with known gestational age (calculated by obstetrical methods). The fetal measurements were measured as per the standard protocol. Results: The study showed that there is a good correlation between gestational age and FL, HC, CRL, CHL and AC. FL was more accurate in assessing GA followed by HC, CRL, CHL and AC. The correlation coefficients of the equation & standard error of the estimate were 0.922 &2.41088, 0.901& 2.70397, 0.878 &2.97715, 0.900 &2.77665 and 0.886 & 2.89121 respectively for FL, HC, CRL, CHL and AC. Conclusion: We conclude that fetal measurements like FL, HC, CRL, CHL and AC are reliable for estimation of fetal age. FL is more accurate than other fetal parameters for estimation of GA followed by HC, CRL, CHL and AC.
Antenatal fetal age estimation by measuring Crown-Rump Length, Bi-Parietal Diameter and Femur Length
IP Innovative Publication Pvt. Ltd., 2017
Introduction: The gestational age estimation is an essential part of the care and management of pregnant women. A number of methods have been used for fetal dating and ultrasonography have become as an integral part of Obstetrics. Objective of this study is to determine whether Ultrasonography (USG) based Expected date of delivery (EDD) is better or Last menstrual period (LMP) based EDD. Materials and Method: This study was done on randomly selected 50 pregnant women. Cases were selected from those attending antenatal clinic, labour room, Indoor and outdoor of the Department of Obstetrics and Gynaecology, at medical college and hospital Kolkata. The parameters like Crown-Rump Length (CRL), Bi-parietal Diameter (BPD), and Femur Length (FL) were used to determine Gestational Age (GA) during 1 st , 2 nd and 3 rd trimester with help of USG. Result: The CRL was better parameter to determine GA in first trimester and BPD and FL was better parameters to determine GA in second and third trimester for gestational age estimation. The CRL, BPD and FL parameters together give the best assessment of GA in Uterus. Conclusion: USG is a better diagnostic tool for estimation of EDD than the LMP method.
Background: Assessment of fetal gestational age with ultrasound provides high accuracy and reliability, as ultrasound is safe, easy operating and cheap. Objectives: to predict the GA with BPD and FL, to derive equations from linear regression analysis of GA with BPD and FL this could be applied to determine the fetal GA, to compare between BPD and FL. Methods: there were 100 normal pregnancies (singleton) had been selected for the study during the second and third trimesters. They were scanned with ultrasound using 3.5 MHz probe applying the obstetrics protocol to measure the fetal biometrics. The length of femoral diaphysis was measured from upper end to lower end excluding epiphysis. The biparietal diameter was measured from the fetal skull when being in oval shape; two thalami should be equal in size. The diameter was drawn from inner to outer margins of the skull perpendicular to the thalami. Results: statistical tests such as correlation and linear regression had been used to get the correlation coefficients and linear equations. There was a strong positive correlation between gestational age and femoral length and biparietal diameter (r = 0.97, r = 0.98). The estimation of gestational age from biparietal diameter could be calculated from the equation GA= 3.385+0.359BPD, and the estimation of gestational age could be calculated from the equation GA= 7.890 + 0.388FL. The most accurate most accurate equation to estimate the fetal gestational age was derived from the equation GA= 4.970 +0.157FL+0.218BPD. Conclusion: The estimation of gestational age with fetal biparietal diameter and femoral length still remain the most common measurements to assess the fetal growth. Evaluation of gestational age with biparietal diameter and femoral length joined together is more accurate than biparietal diameter and femoral length when used separately.
Annals of International medical and Dental Research, 2018
Background: Fetal head circumference (HC) is an important and most reliable individual parameter, which can be used not only for determining fetal age, but also fetal growth and the type of growth restriction-symmetrical or asymmetrical. Objectives: 1) To establish a reference table for fetal head circumference in normal pregnant women from 20 to 38 weeks of gestation from Belagavi District, Karnataka,India 2) To find out the predictive accuracy of gestational age determined by fetal head circumference with gestational age determined by Last menstrual period (LMP) method. Methods: The data was collected by using predesigned pretested questionnaire from September 2016 to January 2018. Total 768 singleton pregnant women with minimum 30 cases for each gestational week from 20 to 38 weeks of gestation, fulfilling inclusion and exclusion criteria were studied. Statistical Analysis: The data was analyzed using Statistical Package for Social Sciences (SPSS) version 20. Percentages, Mean, Standard Deviation and range, standard error, percentiles and regression equation etc. were performed for head circumference for each gestational week. Results: The regression equation derived was GA =-0.254 + (1.130 X HC in cm). By this regression equation, the accuracy in prediction of gestational age by head circumference measurement was ranging from 99.27% at 23 weeks to 92.64% at 38 weeks of gestation. The observed difference in mean HC values in present study and that of Hadlock's was 0.09 cm at 20 weeks of gestation which went on increasing with advancing gestational age-0.69 cm, 1.36 cm, 1.62 cm and 2.09 cm at 30, 35, 36 and 38 weeks of gestation respectively, which was statistically significant. Conclusion: The present study findings confirmed that the fetal head circumference measurements significantly vary among different population groups due to genetic, racial, and ethnic factors. So generation of population specific reference tables and regression equations for various fetal biometric parameters by a large scale study at national level is required for more precise reporting of gestational age and Expected date of delivery (EDD) by ultrasonography.
The study was carried out to assess fetal gestational age with the help of ultrasonographic measurements of different fetal biometric parameters [i.e. Biparietal diameter (BPD), Femur length (FL), Abdominal circumference (AC)] and Fetal kidney width ( KW ), in 199 women with singleton uncomplicated pregnancies attending the O.P.D for routine ultrasound fetal biometry in western Uttar Pradesh (UP). Above fetal parameters were measured biweekly, between 18 and 38 weeks of gestation. Linear regression models for estimation of gestational age were derived from above fetal biometric parameters. The linear regression model for estimating fetal gestational age is femur length, abdominal circumference, fetal kidney width and biparietal diameter in that order with standard error of ± 3.85, ± 4.85, ± 5.81 and ± 8.75 days respectively. Key words: Gestational age, Biparietal diameter, Femur length, Abdominal circumference and fetal kidney width
The Professional Medical Journal
Objective: To compare correct assessment of gestational age betweenTranscerebeller diameter versus femur length in third trimester (28-40) using first day of lastmenstrual period for actual period of gestation. Study Design: Cross-sectional descriptive study.Place and Duration of Study: Department of Obstetrics and Gynecology, Bahawal VictoriaHospital, Bahawalpur from Jun 2012 to Dec 2012. Methodology: This study was performed on327 patients in third trimester of pregnancy from 28-40 weeks fulfilling the inclusion criteria.Ultrasound measurements of transcerebellar diameter (TCD) and femur (FL) were made withcommercially available real time ultrasound equipment Toshiba Nemio-10 model 2009,Transducer frequency 50/60 Hz. Collected data was analyzed by SPSS version 10. Results: Outof 327 patients, TCD was found to give correct assessment corresponding to the gestational ageby LMP in 262 (80.1%) patients, while in 232 (70.9%) patients FL was found to give correctassessment corresponding...
A Study of Sonographic Evaluation of Fetal Femur Length for Estimation of Gestational Age
International Journal of Anatomy and Research
Introduction: Accurate estimation of Gestational age is of great value in proper obstetric care and intervention during pregnancy. Ultrasound has evolved as a reliable method for accurate measurement of gestational age by measuring various fetal biometric features like Crown Rump Length (CRL), Biparietal Diameter (BPD), Femur length (FL), Abdominal Circumference (AC), Head Circumference (HC), Trans Cerebellar Diameter (TCD) etc. Femur being the longest bone in fetus, least movable and easily imagable from second trimester to delivery, can be measured for estimation of gestational age. The present study was performed to evaluate femur length in second and third trimester by ultrasonography, assess gestational age from measurement of Femur Length (FL) and determine the accuracy of gestational age assessed by ultrasonography with gestational age assessed by LMP method in local population of Gujarat. Materials and Methods: Cross sectional study of total of 200 pregnant women, 100 second trimester and 100 third trimester, between 13 and 40 weeks of gestational age attending the department of radiology at P.D.U. Medical college, Rajkot for a fetal ultrasound scan was done. Femur length (FL) was measured; Gestational age was measured by Hadlock's method and Loughna P et al's method; also gestational age was assessed from LMP of the women. The mean values of femur length and predictive accuracy of fetal femur length was analyzed and compared with other studies. Results: Mean of FL increased progressively from 13-40 weeks of gestation. During both second and third trimesters, Hadlock's formula and Loughna P's method were equally accurate to assess the gestational age. But femur length was more accurate in second trimester than in third trimester. There was discrepancy in values of femur length as compared to other studies. Conclusion: Like other studies the present study also found the need of fetal charts that were specific for individual population and ethnic group to determine gestational age and EDD to enable the development of better clinical guidelines for the present population.
BJOG: An International Journal of Obstetrics and Gynaecology, 1986
The use of femur length (FL) and biparietal diameter (BPD) for estimation of gestational age (GA) was investigated using 1123 ultrasound measurements between the 14th and 41st week of gestation. Femur length was found to provide a more accurate index than BPD for the entire range of gestational age considered. If an interval of approximately k 2.5 weeks is considered 'satisfactory', the accuracy of FL past the 31st week is not sufficient to justify its use. Combining the FL and BPD measurements via the formula: GA = 9.565 + (0.0414) FL + (0-0024573) FL' + (0.15209) BPD -(0.00015827) BPD2 provides an index of gestational age accurate to approximately & 2.5 weeks up to the 32nd week of gestation and accurate to approximately f 2.75 weeks up to the 34th week of gestation. This is the first time that combining FL and BPD in a statistically rigorous manner has been proposed as an index of gestational age, and we suggest that this combination be used as a routine tool in its assessment.
Evidence Based Women's Health Journal, 2021
Background: Routine sonographic examination is the cornerstone in estimation of gestational age (GA) and management of pregnancy, using Biparietal diameter (BPD), femur length (FL) and Abdominal circumference (AC) ،but there are limitations with using such parameters. fetal cerebellum exhibits a progressive growth throughout the gestation period. So, it is an organ capable of providing information on the prediction of gestational age during the pregnancy this study has evaluated the accuracy of trancerebellar diameter (TCD) over other parameters of gestational age between 30-40 weeks. Aim: The study aims to evaluate the accuracy of TCD in singleton gestation as an accurate parameter compared to other parameters (Fl, BPD, AC) and Hadlock equation in determining gestational age in normal pregnant woman and normal fetus. Materials and Methods: This cross-section study was conducted on 100 pregnant women between 30 to 40 weeks of gestational age who attended the antenatal care in the outpatient clinic at Ain-Shams university maternity hospital in the period from September 2018 to September 2019. The whole patients were fulfilling the inclusion and exclusion criteria and counseled for the study and then ultrasound examination and measurements of the TCD, BPD, FL and AC were recorded, GA by different parameters (TCD, FL, BPD and AC) and GA by Hadlock were compared to GA by last menstrual period (LMP). Results: In our results the TCD was accurate within 1 week in 91% of the cases and was accurate within 3 days in 59% of the cases. While the FL was accurate within 1 week in 82% of the cases and was accurate within 3 days in 51% of the cases. The BPD was accurate within 1 week in 70 % of the cases and within 3 days in 39% of the cases. Finally, the AC was accurate within 1 week in 65 % of the cases and within 3 days in 37% of the cases. Also, GA by TCD and Hadlock equation showed highest correlation with GA by LMP followed by FL and BPD and least accurate was AC. Conclusion: From the study, we can conclude that TCD is the most accurate method for assessment of gestational age in third trimester followed by FL then BPD and the least accurate is the AC. Also, by combining accuracy of TCD (91%) and that of FL (82%) we can be near certain of gestational age in most of our patients even if they are unsure of their dates. Furthermore, TCD and GA by Hadlock equation showed similar accuracy in gestational age assessment. In all methods the accuracy was higher in <35 week than ≥35 week of gestational age. We recommend to conduct this study on larger sample size for further documentation of the proposed assumption.