PATIENT INFORMATION- FIRST TRIMESTER SCREENING FOR CHROMOSOMAL AND STRUCTURAL MALFORMATIONS: THE 10-13 WEEK SCAN

Brief overview...

• The vast majority of babies are born normal.
• All women, whatever their age, have a small risk of delivering a baby with physical and/or mental handicap.
• In some cases the handicap is due to a chromosome abnormality such as Down syndrome (Trisomy 21) or Trisomy 18.
• First Trimester Screening (FTS) gives an estimate of the risk for Down's syndrome. To know for sure whether or not the fetus has a chromosome abnormality, an invasive test is needed (chorionic villus sampling or amniocentesis- see over). However, invasive tests carry risk of causing miscarriage.