Additional Study Information: The purpose of this study is to collect blood samples from women who are pregnant with a fetus that has been confirmed by prenatal microarray testing to have a chromosomal abnormality, such as a microdeletion (missing chromosomes) or microduplication (extra chromosomes). The sponsor of this study, Sequenom Laboratories, will use these samples to develop and optimize a noninvasive blood test that could identify such abnormalities in other women without the need for an invasive procedure.