Trisomy 18 is due to the presence of an extra copy of chromosome 18. Trisomy 18 is the cause of Edwards syndrome and is associated with a high rate of miscarriages . Babies born with trisomy 18 may have different cardiac birth defects and other medical conditions and a short life span . It is estimated that trisomy 18 is present in about 1 in 5,000 births 1.
- U.S. National Library of Medicine. Genetics Home Reference. Trisomy 18. ghr.nlm.nih.gov/condition/trisomy-18. Accessed July 12, 2012.