First Trimester Ultrasound Screening for Congenital Abnormalities

Abstract

Background: Congenital abnormalities are one of the important contributors to perinatal morbidity and mortality worldwide. The prenatal screening for these conditions is one of the major aims of a good antenatal unit. Over the years there has been a gradual change in the
approach used, especially with the introduction of first trimester ultrasound as a reliable screening method.
Objective: To give a comprehensive review of the basis for first trimester ultrasound screening for congenital abnormalities, it's utilization in the prenatal screening for chromosomal, structural and genetic abnormalities as well as its limitations.
Source: An electronic database search and review of relevant literatures with the use of the following keywords: first trimester screening, ultrasound scan, nuchal translucency and prenatal screening. Manual search was also conducted for recent issues of key journals and current texts.
Conclusion: The first trimester scan has been proven to be an equally effective method of prenatal screening for congenital abnormalities compared to older methods of screening. It is recommended for implementation in antenatal units especially in developing countries. There
is however, the need for proper training and regular auditing of results to achieve the best result.

Key words: First trimesters scan, Nuchal Translucency (NT), Prenatal screening, Congenital
abnormalities.