ultrasound scan (in prenatal diagnosis)

Last reviewed 01/2018

An ultrasound scan is a non-invasive technique that has no associated risk for mother or fetus. Is the following undertaken to detect conditions which are detectable, although sometimes only with serial scans:

  • CNS: anencephaly, spina bifida, hydrocephalus, microcephaly
  • limb: severe short-limbed dwarfism, polydactyly, osteogenesis imperfecta
  • heart: severe congenital heart disease
  • kidney: renal agenesis, bladder outflow obstruction, infantile polycystic disease
  • GIT: duodenal atresia, anterior abdominal wall defects, diaphragmatic hernia

Specific markers for chromosomal abnormalities include is an increased nuchal fold. Also bright bowel can alert to the suspicion of a pregnancy at risk of cystic fibrosis, if seen on scan screening both parents would be discussed.

An anomaly scan to pick up structural defects can be performed between 18+0-20+6 weeks.