What causes a chromosome abnormality?
In some cases, a parent may carry a chromosome abnormality that is passed to his or her child. However, in most cases, chromosome abnormalities are de novo events. This means that the chromosome abnormality was not inherited from a parent. Rather, it is a change that was present at conception in either the egg or the sperm Many families wonder why their baby was born with a chromosome abnormality.Although we know that the chromosome change was present in the egg or the sperm, we still do not know why that change happens in the first place. Research studies have looked at many different factors, including chemical exposures, geographic location, and ethnicity. Up to this point in time, none of these studies have shown that these factors cause chromosome abnormalities. We do know, however, that, as women age, they have a greater likelihood of having a baby with a full extra chromosome. As discussed above, this is called a trisomy. Although this risk may increase with age, it is important
