Down's, Edwards’ and Patau’s syndrome screening

 

Alternative names, keywords

Trisomy 21, trisomy 18, trisomy 13, first trimester screening.

Samples required

Clotted blood (gold cap, 5 mL tube). Transport promptly to laboratory.

Blood samples are taken as necessary via antenatal departments following ultrasound imaging, and must be accompanied by the correct request form. Full completion of this request form is essential for risk calculation.

Test indications

Combined screening for Downs, Edwards’ and Patau’s syndrome is done as part of the BSUH Fetal Anomaly Screening programme, between 11 weeks and 2 days to 14 weeks and 1 day of gestation.

If this window is missed, samples can be referred for second trimester screening (see below).

Reference range

See report.

Turnaround time

3 working days

Enquiries

Biochemistry (Special Chemistry)

 

Second trimester Down's screen

Referred to Antenatal Screening Service, Wolfson Institute, Barts and The London, Queen Mary School of Medicine and Dentistry, Charterhouse Square, London EC1M 6BQ
 

Alternative names, keywords

Quadruple test

Samples required

Clotted blood (gold cap, 5 mL tube) at 16 to 18 weeks amenorrhoea.

Test indications

Down's screening in second trimester.

Reference range

See report.

Turnaround time

Referral lab quotes turnaround time of 1 day, however additional time must be allowed for packing, dispatch and delivery of sample, and return and processing of results.

Enquiries

Biochemistry (Special Chemistry)