Infectious Diseases in Pregnancy Screening, IDPS, Antenatal Serology
Department of Infection Science (Virology/Serology)
The Antenatal Screening tests include HIV, Hepatitis B Surface Antigen and Treponema pallidum (syphilis) serology. These are tested as part of the screening programme.
Highlight high risk samples – where the patient is known to test positive for HIV, hepatitis B or Syphilis, please provide this in the supporting clinical details.
Samples should be collected according to standard phlebotomy practices. Please refer to phlebotomy page of this website for further detail. There are not specific instructions for collection of blood samples for Infectious Diseases in Pregnancy Screening samples other than ensuring correct vacutainer is used.
Packaging must be compliant with Dangerous Good Safety Advisor (DGSA) requirements click here for more information.
Where the sample waits before being sent to the laboratory, less than 4 hours to sample collection room temperature will suffice, Greater than 4 hours to collection refrigerate at 2 – 6 ⁰C.
4ml clotted blood (1ml if paediatric), red top or gold top adult vacutainer.
We aim to process and report all samples within 7 days, though in reality the majority are processed and reported within 48 hours. The turnaround time may differ if the sample has to be referred to another testing facility.
Critical Values / Critical Result Communication
Any reactive results are communicated directly to the relevant antenatal screening team for action. This includes all new or known case HIVs, Hepatitis B and Syphilis.
The Antenatal screening team are also notified of any samples which are rejected to allow for repeat tests to be sent if applicable.
Factors that significantly affect result
Haemolysis may impact on validity of results. Any delays to testing can also impact.
Any reactive HIV results will be referred to Virus reference Laboratory at Colindale for further testing to confirm or clarify our in-house results. They are UKAS accredited for the testing performed.
Please ensure that where a sample is sent and the patient has not consented for HIV testing, or any testing at all, that this is clearly stated on the request form.
Please note that the laboratory element of this pathway is assessed separately by UKAS and ensures that the processes conform to the ISO15189:2022 standard and the Infectious Diseases in Pregnancy Screening Standards. More information can be found on the government website
Infectious diseases in pregnancy screening (IDPS): programme overview - GOV.UK
The laboratory criteria for acceptance and rejection of requests aligns with the UHNM Trust Policy Requesting Patient Investigations and Referrals and the Reporting of Results in conjunction with the Infectious Diseases in Pregnancy Screening Laboratory Handbook.
Information and guidance for requesting using electronic requesting systems can be found using the links on the main page of the Pathology Website.
Information relating to the protection of personal information and the laboratory complaints procedures can be found using the links on the main page of the Pathology Website.
