In the first half of a pregnancy testing of fetus is for the purpose of detecting abnormal chromosomal conditions or inborn errors. Later in pregnancy certain high risk conditions in either the mother of the fetus lead us to perform tests of fetal wellbeing to be sure that the fetus is not in jeopardy.
Before you consider any testing, you should consider the question, “How will this information affect how I manage my pregnancy?” Your answer to that question will affect how you view these tests. Your choice of testing is personal.
Certain conditions in pregnancy can compromise the environment of the unborn child. In the final trimester we often do testing in women in whom a high risk condition has been identified to be sure that their baby is not affected.