Nursing care
Newborn Screening: the nurse's role, start to finish
Written and reviewed by Dana Whitfield, RN, MSN · 6 min read · Updated September 2026
Short answer
Newborn screening nursing management means timing the heel stick correctly, collecting an adequate blood spot, and following up abnormal results without delay. The sample should be taken after at least 24 hours of feeding, because several metabolic markers, including phenylalanine, are not reliably elevated before the infant has taken in protein.
Indications and contraindications
Newborn screening is offered to every infant born in the United States, regardless of gestational age, feeding method, or apparent wellness. It is not diagnostic; it is a population-level sieve for metabolic, endocrine, haematological and other congenital conditions that have no visible signs at birth but cause irreversible harm if treatment is delayed. Conditions vary by state panel but commonly include phenylketonuria, congenital hypothyroidism, sickle cell disease, cystic fibrosis, and several fatty acid oxidation disorders.
There is no true contraindication to the screen itself, but timing needs adjusting in specific situations. Infants who are transfused before the first sample is taken need a second screen after the transfused cells have cleared, because haemoglobinopathy and some enzyme results are unreliable in mixed blood. Infants on parenteral nutrition or those who have had minimal enteral feeding by 24 to 48 hours still need the screen, but a nurse should flag the feeding history on the requisition so the lab interprets amino acid levels correctly. Preterm infants are screened on the same schedule as term infants and then rescreened at two weeks or discharge, whichever comes first, because immature metabolism can mask abnormal results on the first pass.
Getting the patient ready
Preparation starts with feeding, not with the heel itself. The sample should be collected after the infant has had at least 24 hours of feeding, whether breast or formula, because protein intake is what raises phenylalanine and several other amino acids to detectable levels. A heel stick performed too early, before the infant has taken in enough protein, can return a false negative for phenylketonuria and other aminoacidopathies even when the underlying condition is present. Nurses should check the feeding record before drawing the sample and document the time of first feed alongside the time of collection.
Warming the heel improves flow and reduces the number of squeezes needed, which in turn reduces haemolysis and tissue fluid contamination. A warm compress or commercial heel warmer applied for three to five minutes is standard. The infant should be positioned with the foot dependent, and a support person or second staff member can hold the leg still if the infant is unsettled. Skin should be cleaned with alcohol and allowed to dry fully before the puncture, since residual alcohol dilutes the specimen and can affect enzyme assays.
Technique and safety checks
The puncture site is the lateral or medial plantar surface of the heel, avoiding the central weight-bearing area and any site used for a previous stick, to reduce the risk of calcaneal osteomyelitis. A spring-loaded lancet with a depth appropriate for a term or preterm infant is used rather than a manual blade, since it standardises depth and reduces bone injury. The first drop of blood is wiped away, as it may contain tissue fluid, and subsequent drops are allowed to form naturally rather than being forced by hard squeezing, which causes haemolysis and haemodilution.
Each circle on the filter card must be filled from one side only, with a single application of blood soaking fully through to the back of the card, confirmed by checking both sides before the card dries. Layering blood on top of an already-drying spot produces a specimen the lab will reject. Two identical patient identifiers are checked against the card before and after collection, and the card is air-dried horizontally on a non-absorbent surface for at least three hours before it is sent, since heat, direct sunlight and contact with other wet cards all degrade the sample.
What can go wrong
Insufficient specimen volume is the most common reason a card is rejected, usually from squeezing too hard, moving between drops, or filling a circle from both sides so the blood does not saturate through. Contamination from alcohol, powder, or hand cream on the collector's gloves can also alter results. A card collected too early, before 24 hours of feeding, risks a false negative that will not be caught unless the repeat screen at two weeks picks it up, which is one reason repeat screening exists for preterm and early-discharge infants.
Calcaneal osteomyelitis and perichondritis are rare but documented complications of repeated or deep heel sticks, particularly when the same site is reused. Bruising and localised swelling are common and usually resolve without intervention. A card that arrives at the laboratory more than the specified window after collection, typically 72 hours in most state protocols, may be flagged for degraded analytes, so postal delays over a weekend are a genuine operational risk that nursing staff should account for when discharge falls on a Friday.
Ongoing care
The nurse's responsibility does not end when the card is sent. Parents need clear, written instructions on how and when they will be notified of results, since most infants are discharged before the screen is finalised. They should be told that a normal result usually means no contact, while an abnormal or borderline result triggers a call from the state programme or the paediatrician, often within days, and requires prompt follow-up testing rather than panic.
Any infant discharged before 24 hours of feeding, or before the screen was collected at all, needs a documented plan for repeat testing, usually at the first outpatient visit within 48 to 72 hours. Nurses coordinating discharge should confirm the screen was drawn, confirm the timing was adequate, and hand off that information explicitly to the receiving primary care team, since a missed newborn screen is one of the more common and most preventable gaps in postnatal care.
Common exam questions
NCLEX-style questions on newborn screening usually test three things: correct timing relative to feeding, correct technique to avoid contamination or haemolysis, and correct interpretation of what an early or inadequate sample means for results. A question describing a heel stick performed at two hours of age, with no mention of feeding, is testing whether the candidate recognises the risk of a false negative rather than a technique error.
Expect scenario questions where the distractors include drawing venous blood instead of capillary, using the central heel pad, or sending a card that has not fully dried. The safe answer is almost always the option that delays or repeats testing rather than accepts a questionable sample, since newborn screening prioritises sensitivity over convenience. Questions may also test discharge planning, asking what the nurse should do when an infant is being discharged early and has not yet reached 24 hours of feeding.
The next step on this is the same as on everything else here: answer questions and read the rationales. Our maternity and newborn practice questions are the closest set to what this page covers.
Common questions
Can newborn screening be done before 24 hours of age?
It can be collected earlier if the infant is being discharged, but professional guidance recommends waiting until at least 24 hours of feeding wherever possible, because phenylalanine and other markers may not yet be elevated. If an early sample is unavoidable, the infant needs a repeat screen at two weeks or the first follow-up visit.
What should a nurse do if the newborn screening card is rejected for insufficient sample?
Contact the family to arrange a repeat heel stick as soon as possible, ideally within a few days, since a rejected card means the infant is effectively unscreened. Document the reason for rejection and confirm the family understands this is a lab requirement, not a sign anything is wrong with the baby.
Does breastfeeding versus formula feeding affect newborn screening results?
Both provide the protein intake needed to raise amino acid levels to detectable thresholds, so either is acceptable before collection. What matters is that feeding has occurred for at least 24 hours, not the specific type of milk.
Why is the heel used instead of a venous draw for newborn screening?
The heel stick is less invasive for a neonate, avoids the technical difficulty of venous access in very small veins, and provides sufficient capillary blood for the filter card method most state laboratories use. Venous sampling is reserved for confirmatory testing after an abnormal screen.
What happens if a preterm infant cannot tolerate feeds by 24 hours?
The initial screen is still collected on the standard newborn schedule, but the feeding status is documented, and the infant is scheduled for a routine repeat screen at two weeks of age or at discharge, whichever is sooner, to catch any result that was falsely reassuring on the first pass.