A diagnostic peripheral maternal blood test taken and the free foetal DNA is analysed and the presence of trisomies using a novel method.

A total of ~2000 participants have donated blood samples used for the development and validation of the IONA non-invasive prenatal screening test for Downs, Edwards and Patau syndrome. The IONA Test was CE marked Feb 2013. We are now recruiting a further 800 participants to provide blood samples to further develop and verify the test for other chromosomal abnormalities and to improve test efficiency.

Inclusion Criteria:

• Patient/subject is willing and able to give informed consent for participation in the study.
• Female, aged 16 years or above.
• Currently pregnant at time of entry to the study.
• Pregnancy having been identified as 'high-risk' by screening test.

Exclusion Criteria:

• The patient/subject may not enter the study if ANY of the following apply:
• The participant herself has Down's Syndrome or other chromosomal abnormality.
• Children under 16
• Adults with learning disabilities
• Adults who are unconscious or very severely ill
• Adults who have a terminal illness
• Adults in emergency situations
• Adults suffering from a mental illness
• Adults with dementia
• Prisoners
• Young offenders
• Adults who are unable to consent for themselves
• Any person considered to have a particularly dependent relationship with investigators

Mothers attending clinic for routine screening. Followed up at around 1 years duration.