Addmark^TM

Earliest Week: 10
Latest Week: 13

Price: £195

This includes a nuchal scan as described previously combined with a blood test taken between 10 – 13 weeks. 

Four biochemical blood markers and the nuchal measurement are used to calculate the risk of Down’s syndrome and other chromosomal abnormalities. A second blood sample looking at a further 4 biochemical markers is offered to those patients whose risk falls between 1 in 50 and 1 in 1500. Overall the detection rate is 90% and the false positive rate of 1%.

Screen negative is final a risk less than 1 in 250.