Objective

onographic markers are widely used for aneuploidy screening. Shortening of the fetal long bones such as the humerus and femur is a sonographic soft marker for screening of Down syndrome in the second trimester. Ethnic differences in fetal biometric measurements have been documented. [1][2][3] Beigi and ZarrinKoub 3 reported that Iranian fetuses had a shorter femur length in comparison with western studies. Kovac et al 1 concluded that Asian groups had a less-than-expected femur length.Undoubtedly, ethnic differences in fetal femur and humerus diaphysis length would have a considerable impact on Down syndrome screening; in one study, positive sonographic results were reported more frequently in nonwhite ethnicities because of shorter long bones. 2 In our previous study, we obtained normal ranges for the fetal nasal bone during the second trimester of pregnancy. 4 The aim of this study was to provide normal ranges for femur and humerus diaphysis length during the second trimester in an Iranian population. -Reza Tahmasebpour, MD, Reihaneh Pirjani, MD, Abbas Rahimi-Foroushani, PhD, Saeed Reza Ghaffari, MD, Fatemeh Rahimi-Sharbaf, MD, Farzaneh Fattahi Masrour, MD Received November 18, 2011, from the Iranian Fetal Medicine Foundation, Tehran, Iran (A.-R.T., S.R.G., F.F.M.) Ahmad ORIGINAL RESEARCHObjectives-Shortening of the fetal long bones is a sonographic soft marker for screening of Down syndrome in the second trimester that can be influenced by ethnicity. The purpose of this study was to provide normal reference ranges for femur and humerus diaphysis length during the second trimester of pregnancy in an Iranian population.Methods-This cross-sectional study was performed on 3011 singleton fetuses at 15 to 28 weeks' menstrual age. The relationship between menstrual age and both femur and humerus diaphysis length was determined, and percentile values for each menstrual week were provided.Results-The median femur diaphysis length ranged from 18.05 mm at 15 menstrual weeks to 52.20 mm at 28 menstrual weeks, and the mean humerus diaphysis length ranged from 17.65 mm at 15 menstrual weeks to 48.10 mm at 28 menstrual weeks. There was a linear relationship between menstrual age and both femur diaphysis length (R 2 = 0.957) and humerus diaphysis length (R 2 = 0.941).Conclusions-We have provided normal reference ranges for femur and humerus diaphysis length during the second trimester of pregnancy in an Iranian population.

No abstract

We have provided the normal reference range for NBL during the second trimester in an Iranian population. NBL in singleton and twin fetuses is similar and there is no significant difference between twins regarding NBL.

The corpus callosum (CC) is the major interhemispheric commissure and its abnormalities include agenesis, hypoplasia, and hyperplasia. The CC anomalies are typically related to other central nervous system (CNS) or extra-CNS malformations.The antenatal diagnosis of complete CC agenesis is easy after mid-trimester by ultrasound (US) even in the axial plane. The non-visualization of cavum septum pellucidum and colpocephaly are critical signs in the axial view. More subtle findings (i.e., hypoplasia and partial agenesis) might also be recognized antenatally. In this review, the focus was given on the prenatal diagnosis of CC abnormalities in US and magnetic resonance imaging.