How does trisomy 18 affect a person?
WHAT IS TRISOMY 18?
Trisomy 18, also known as Edwards syndrome, is a condition which is caused by a error in cell division, known as meiotic disjunction. When this happens, instead of the normal pair, an extra chromosome 18 results (a triple) in the developing baby and disrupts the normal pattern of development in significant ways that can be life-threatening, even before birth.
Sometimes the mother's egg or the father's sperm contains the wrong number of chromosomes. As the egg and sperm combine, this mistake is passed on to the baby.
A "trisomy" means that the baby has an extra chromosome in some or all of the body's cells. In the case of trisomy 18, the baby has three copies of chromosome 18. This causes many of the baby's organs to develop in an abnormal way.