Clinical Evaluation of the IONA Test for Non-invasive Pre Natal Screening in Twin Pregnancies

Clinical Evaluation of the IONA Test for Non-invasive Pre Natal Screening in Twin Pregnancies

The purpose of this study is to evaluate the performance of the IONA® test which is a non-invasive prenatal test (NIPT) for Down's syndrome and other chromosomal abnormalities in twin pregnancies, from a maternal blood sample.

350 low risk and 150 high risk women with twin pregnancies will be recruited to produce a large cohort evaluation the use of the IONA test in twin pregnancies for Downs, Edwards and Patau syndrome. Reserve samples will also be used to further develop the test for other chromosomal abnormalities.

Inclusion Criteria:

• Currently pregnant with twin foetuses at time of entry to study
• Have had or are about to have a conventional screening test (combined/quad test, ultrasound scan or other NIPT)
• If identified as high risk, intend to undergo prenatal invasive diagnosis and/or undergoing invasive prenatal therapy such as laser treatment for TTTS where a sample of amniotic fluid is taken for karyotyping.

Exclusion Criteria:

• Participant herself has down syndrome or other chromosomal abnormality