Tag: defects
Teratogen
by admin on Mar.27, 2010, under Women's Health
Introduction
Teratogen is a substance, organism, physical agent, or deficiency state present during gestation that is capable of inducing abnormal postnatal structure or function (biochemical, physiologic or behavioral) by interfering with normal embryonic or fetal development and thus, disturbs fetal development if fetal exposure to these agents occurs during pregnancy. A child born with any kind of malformation or with any birth defect may create societal problems and therefore this subject needs concern (Blackburn, 2007). It is manifested that approximately 3% of all human newborns have a congenital anomaly requiring medical attention and approximately 1/3 rd of these conditions can be considered as life threatening. Of hospitalized children 40% are due to prenatal malformation (Thomas, 2004). We are only at the tip of the ice-berg to explore out all the reasons of these malformations. 25% are associated with gene mutation, 5% are associated with chromosomal aberrations, and 10% of the anomalies are due to teratogenic agents (Thomas, 2004). It is evident that huge gaps exist between our understanding and the role these agents play to cause human malformation (Thomas, 2004).
Any agent can be categorized as a teratogenic agent if it is capable of creating congenital defect. A congenital defect or anomaly is a kind of major or minor deviation from normal morphology or function and are generated during fetal or embryonic development (Jones, 2004). Minor defects are found in 2-3% of the population while large morphological types of congenital defects like cleft palate or meningomyelocele are the defects that alter function. A change in functions is also attributed to molecular mechanisms. Altered function of nervous and endocrine systems or in postnatal function is the main concern for both experimental and human teratology (Thomas, 2004).
Koch
