TY - JOUR T1 - Study of Sonographic Value of Biparietal Diameter as a Parameter for Estimation of Gestational Age in Tehran Mirza Kuchak Khan Hospital and Hamadan Fatemieh Hospital in 1994 TT - بررسی ارزش سونوگرافیک (Biparietal diameter) بعنوان معیاری برای تعیین سن حاملگی در مراجعین به بخش سونوگرافی بیمارستانهای میرزاکوچک خان تهران و فاطمیه همدان در سال 1373 JF - umsha JO - umsha VL - 7 IS - 1 UR - http://sjh.umsha.ac.ir/article-1-953-en.html Y1 - 2000 SP - 0 EP - 0 KW - Fetal Development / Gestational Age / Ultrasonography KW - Prenatal N2 - Accurate knowledge of fetal age is very important . A number of methods can be used to determine an accurate gestational age . With routin use of ultrasonography more information about the anatomy of the fetus can be obtained . one of the parameter that can be used is biparietal diameter . This study was carried out in 386 pregnant women with known last menstrual period . Regression analysis was performed to evaluate the relationship between biparietal diameter and menstrual age. Regression analysis indicated that menstrual age could be predicted with3.5 weeks with 95% interval confidence.This was also computed for three gestational age interval : 20-26 weeks , 26 - 32 weeks and 32-42 weeks.The results indicated that prediction of age become progressivly less accurate as pregnancy proceed . M3 ER -