Assessment of Gestational Age Using Ultrasound
Determining gestational age in resource-poor settings is challenging because of limited availability of ultrasound technology and late first presentation to antenatal clinic. Last menstrual period (LMP), symphysio-pubis fundal height (SFH) and Ballard Score (BS) at delivery are therefore often used. This study explains the relationship between MSD, CRL and GA (USG) in the first trimester, BPD, HC, AC, FL and GA (USG) in the second trimester, EFW, BPD, HC, AC, FL and GA(USG) in the third trimester. From the results 3D and 4D USG will improvise the ability to assess early pregnancy viability and multiple gestations.
KeywordsGestational age, Ultrasound
Radiographic techniques were generally used to measure fetal dimensions prior to ultrasound, which had the drawback of exposing radiation to the foetus. Currently with increasing use of ultrasound, a non-invasive diagnostic procedure, there is a decrease in maternal morbidity and mortality. Ultrasonography is commonly used to estimate gestational age by measuring fetal dimensions like gestational sac diameter, crown rump length, biparietal diameter, abdominal circumference, head circumference and femur length. Hence this study aims to measure these fetal parameters and to obtain accurate gestational age [1-5].
The study this study, 145 antenatal women were selected, observed, and underwent physical examination, lab investigations to rule out maternal diseases. patients were subjected to ultrasonogram, and the Gestational age was determined by measuring fetal parameters.
The percentage of gestational age classes are depicted in Figure1 To prove a correlation between the fetal parameters in the second and third trimester with gestational age a correlation coefficient was calculated and found to be 0.995, 0.995, 0.993, 0.997 and the values were less than 0.001, thereby showing a positive correlation between these variables. gestational age a correlation coefficient was calculated and found to be 0.995, 0.995, 0.993, 0.997 and the values were less than 0.001, thereby showing a positive correlation between these variables.
Figure 1. Percentage of gestational age classes.
Table1 explains that both CRL and MSD were contributing towards gestational age assessment and highly significant. BPD and FL were highly significant.
|GA BY USG||BPD||FL||HC||AC|
|Pearson Correlation||GA BY USG||1||0.995||0.995||0.993||0.997|
Table 1: CRL and MSD contribution.
HC was excluded in this model since it was not contributing.
Discussion and Conclusion
The study explains that there is a linear relationship between MSD, CRL and GA (USG) in the first trimester, BPD, HC, AC, FL, and GA(USG) in the second trimester, EFW, BPD, HC, AC, FL and GA(USG) in the third trimester. In case of abnormal measurements of fetal parameters disease conditions should be addressed. Multiple parameters should be used to assess gestational age. It is likely that the technological development of USG will continue and increases in ultrasound frequency will further improve image resolution of early pregnancies. 3D and 4D USG will also improve our ability to assess early pregnancy viability and multiple gestations [6-10].
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Citation: G Rajathi, Assessment of Gestational Age Using Ultrasound , J Res Med Dent Sci, 2021, 9(8): 64-65
Received: 14-Jul-2021 Accepted: 02-Aug-2021