Data section 2.2: Updated table outlining the detection rates for the various physical and serious cardiac conditions to reflect the most up to date standards.

Changed the second image under 'Example 2' in the quality assurance chapter.

Added clarification that publication was previously published by Public Health England.

Updated reference of PHE to NHS England

Changed contact email. Added wording to provide clarity on IVF pregnancies and age of donor Added information on measurements for combined and quadruple tests in twin pregnancies Amended wording for the 20-week screening scan. Amended wording for completing the 20-week screening scan to provide clarity to when the rescan should be offered.

Minor amends made to a few pages in the Screening for Down’s syndrome, Edwards’ syndrome and Patau’s syndrome HTML piece and a revised edition of the Request form and data fields required for Down’s syndrome, Edwards’ syndrome and Patau’s syndrome screening form.

Updated links in all sections. Additional information on the quadruple test (screening for Down's, Edward's and Patau's section). Updated information on the PND procedure timeframe (prenatal diagnosis section). Clarification of the image review process (section 4.1 of the quality assurance section). Updates to sections 2.1 and 2.1 of the data section.

Updated education and training chapter, templates for induction of qualified staff (no DQASS report in last 6 months and concerns identified), and template for trainee ultrasound practitioners. Includes new information following the introduction of reporting spread on DQASS feedback plots.

Added more information about annual audit of samples in chapters 2 and 5.

Added lower chance result letter templates.

Added new html version of the screening handbook.

Updated edition of programme handbook valid from August 2018.

First published.