title: Ultrasonic measurement of biparietal diameter and femur in foetal age determination.
abstract: Our objective was to verify ultrasonic measurement of biparietal diameter and femur in foetal age determination in the second and third trimester of pregnancy. The prospective cross sectional study was carried out at the ultrasound department of Aberdeen Maternity Hospital Scotland. The study population consisted of 716 pregnant Scottish (Caucasian) women who were certain of their gestational ages and had their gestational ages confirmed in the first trimester by ultrasound. The findings revealed: (1) Linearity through out pregnancy using the femur length measurements while that of the biparietal diameter demonstrated poor correlation after 32 weeks of gestation. (2) The standard deviation and the correlation coefficient of the femur length measurements were 0.0042 and 0.9920 respectively while the corresponding values for biparietal diameter were 0.0045 and 0.9850 respectively. (3) The standard error for femur length estimate was 0.2251 as against 0.3009 for biparietal diameter estimate. The results suggest that femur length measurement is a more reliable index of late third trimester gestational age prediction than biparietal diameter.
authors.affiliation: Ultrasound Department, Aberdeen Maternity Hospital, Corn Hill Road, Aberdeen, UK.
authors.forename: F O
authors.initials: FO
authors.lastname: Dare
authors.forename: N C
authors.initials: NC
authors.lastname: Smith
authors.forename: P
authors.initials: P
authors.lastname: Smith
mesh_terms: D002508:Cephalometry / Q000592:standards*; D003430:Cross-Sectional Studies; D005260:Female; D005269:Femur / Q000000981:diagnostic imaging*; D005865:Gestational Age; D006801:Humans; D010294:Parietal Bone / Q000000981:diagnostic imaging; D011247:Pregnancy; D011262:Pregnancy Trimester, Second; D011263:Pregnancy Trimester, Third; D012016:Reference Values; D015203:Reproducibility of Results; D016216:Ultrasonography, Prenatal / Q000592:standards*