Evaluation of the lateral ventricle in second trimester is an important indicator for normal brain development. We sought to analyze the difference in the mean fetal lateral ventricle in second trimester among the consanguineous and non-consanguineous marriages in Indian population, in this retrospective cross sectional study. Study was carried out in the Department of Radiology, Sree Balaji Medical College and Hospital, Chennai, from June 2017 – June 2018. A total of 1067 patients in their second trimester (18 – 24 weeks of gestation) were included in this study (740 Non consanguineous and 327 consanguineous marriages). Lateral ventricle measured in true symmetrical axial plane at the atria of lateral ventricle and glomus of choroid plexus, opposite to the parieto occipital sulcus. Mean lateral ventricle dimension was 6.40 mm in consanguineous marriages and 6.42 mm in non consanguineous marriages. There is no significant difference in mean lateral ventricle size in consanguineous marriages and non consanguineous marriages at this period of gestation.