Edwards Syndrome is a genetic abnormality caused by the presence of an extra copy of chromosome number 18. It is, therefore, also referred to as Trisomy 18. In normal cases, human beings have 23 pairs of chromosomes (=46 chromosomes). Even a slight change in this number can lead to severe disorders and abnormalities in the body. Hence, in a normal human, there should be two copies of chromosomes 18, but in someone with Edwards Syndrome, there are three such copies. Edwards Syndrome is not necessarily an inherited disorder. Three copies of chromosome 18 are generated when there is an error during formation of female and male reproductive cells or during early embryonic cell division. Older women have increased chances of giving birth to babies with Edwards Syndrome. Infants born with Edwards Syndrome develop several problems like heart defects, abnormal body growth, etc. even before birth. They have low birth weight, small head with an abnormal shape, and other life-threatening conditions. Chances of survival of such individuals are extremely rare and almost all infants die soon after birth.
Edward's syndrome is caused by meiotic disjunction. This is where there is a problem is cell division that causes a chromosomal defect where you receive three Chromosome 18's. Tri meaning three is where Edward's syndrome got its common name of Trisomy 18.
The causes of Edward's syndrome is when during cell division the baby receives 47 chromosomes as opposed to 46. This occurs during conception.
Due to the extra genetic material it can cause a large amount of problems for a child. Besides having a high mortality rate where around 50% of children carried to term with Edward's syndrome are still born and less than 10% make it to their first birthdays, there is a large range of problems for those who survive past their first year. These include heart defects such as a narrowing of the exit vessel of the heart and a hole in either the upper or lower heart chambers," kidney problems, part of the intestinal tract is outside the stomach, the esophagus doesn't connect to the stomach, excess amniotic fluid, clenched hands, pocket of fluid on the brain, rocker bottom feet, delayed growth, small jaw and head, low-set ears, strawberry-shaped head, severe developmental delays, and umbilical or inguinal hernias."