Send Us a Sample

Samples are collected on day 5 of life on a blood spot card with the date of birth counted as day 0. All sections on the bloospot cards should be completed.  The laboratory operates a strict zero tolerance policy for samples received with a missing or inaccurate NHS number, sample date or date of birth.  We strongly advise checking for transcription errors before sending cards to the laboratory.


Please ensure that the maternity unit code is always included on the bloodspot card to enable acknowledgement of card receipt, efficient collection of repeat cards and accurate reporting of data. 


A good quality blood spot sample is one that is taken at the right time, contains sufficient blood to perform all tests, is despatched to the laboratory in a timely manner and has not been contaminated.


To learn more about completing the bloodspot card visit:



If a baby is to receive a transfusion post delivery, a pre-transfusion sample should be taken for Sickle cell screening. As for other screening test, a lapse of at least 72 hours after the last tranfusion should be allowed before sample collection.


Premature Babies

Babies born at less than 32 weeks gestation (less than or equal to 31+6 days) need a repeat screening test for CHT at 28 days postnatal age (counting the date of birth as day 0) or on day of discharge home, whichever is sooner. Please mark the card 'CHT preterm repeat'. If the sample is taken at discharge before day 28, please mark the card 'discharged home'.


Important information


Once collected, samples should be sent immediately to the laboratory using the pre-paid purple envelope that has our dedicated PO BOX number on it.


Please ensure that the sample is completely dry before inserting it into the glassine and purple envelope.


Consent and Decline


Although screening is recommended, parents have the option of declining one or all tests.


If screening is declined, a completed blood spot card marked 'declined' and stating the reason for decline must be sent to the newborn screening laboratory.


For further details visit:


© 2011 Great Ormond Street Hospital for Children NHS Trust