Newborn Drug Testing - Meconium and Umbilical Cord Tissue

Exposure to maternal drug use during gestation may adversely affect neonatal development and may lead to acute adverse events, including neonatal abstinence syndrome (NAS) and infant mortality. Prenatal drug exposure may also contribute to long-term behavioral effects and developmental deficits. 

Timely detection of in utero drug exposure is critical for effective detection and management of intoxication, withdrawal syndrome, and long-term needs (social and medical) for exposed neonates. 

Detection of drugs depends on extent of maternal drug use, drug stability, drug analyte deposition in meconium and umbilical cord tissue, and performance of the analytical method. 

Quick Answers for Clinicians

When should I consider newborn drug testing?

Newborn drug testing should be considered for infants born to mothers with high-risk behaviors (eg, a history of drug misuse and/or addiction), minimal or no prenatal care, or unexplained obstetric events. Infants with unexplained neurologic complications, intrauterine growth retardations, or drug withdrawal symptoms should also be considered for testing.  Refer to the Newborn Drug Testing algorithm for more information.

Which specimens are acceptable for newborn drug testing?

ARUP offers testing of umbilical cord tissue and meconium. Urine and blood tests are generally not recommended for newborn drug testing. Refer to Available Specimen Types below for more information.

What are the advantages/disadvantages of umbilical cord drug testing and meconium drug testing?

Umbilical cord tissue is easy to collect at birth, drugs deposit evenly across the length of the cord, and the cord grows with the fetus throughout development. Concentrations of some drug analytes are lower in cord than in meconium, but can be detected with the appropriate methodology. Meconium is the traditional newborn drug testing specimen and usually passes within 48 hours of birth. Collection requires coordinated efforts, and detection depends on many factors, including quality and completeness of collection.  Refer to the ARUP Drug Test Table – Meconium and Umbilical Cord for more information.

Which testing algorithms are related to this topic?

Indications for Testing

Newborn drug testing is recommended for infants born to mothers with high-risk behaviors (eg, history of drug use/abuse, prostitution, nicotine use), minimal or no prenatal care, or unexplained obstetric events (eg, placental abruption, premature labor). 

Additionally, infants with unexplained neurologic complications, unexpected intrauterine growth retardation, or drug withdrawal symptoms (eg, NAS) should be tested for drug exposure. 

Available Specimen Types

ARUP offers testing of two specimen types for newborn drug testing: umbilical cord tissue and meconium. Urine as a specimen type for neonatal drug testing has limited success; the first void is often missed because it may occur during or immediately after delivery. Urine tests generally detect only recent maternal drug use in the days prior to delivery.

Newborn Drug Testing Specimen Types  
Meconium Umbilical Cord Tissue

First stool of the newborn

Used for drug testing for ~25 yrs

Begins to form at ~12-16 wks gestation

Accumulates over remainder of pregnancy (nonlinear process)

Usually passes within 48 hrs of birth

Collection requires coordinated efforts and may not be available

Detection depends on many factors (eg, quality and completeness of collection, drug use patterns)

Drugs appear to deposit consistently across length of cord

Forms ~5th wk of gestation

Grows with fetus throughout pregnancy (nonlinear process)

Easy to collect at time of birth

Concentrations of drug analytes are lower in cord than in meconium, but can be detected with appropriate methods

Detection depends on many factors (eg, quality and completeness of collection, drug use patterns)

NOTE: Umbilical cord tissue and meconium drug tests are performed to support clinical and social management decisions and do not usually require chain of custody. ARUP offers a specimen tracking form for documentation of the collection, handling, and shipping of specimens. Contact ARUP Client Services for more information.

There are several factors to consider when selecting umbilical cord tissue vs meconium for drug testing.

Umbilical Cord Tissue vs Meconium Testing
Factors to Consider Umbilical Cord Tissue Meconium

Preferred process for collection is at birth, for all infants; test immediately for high-risk births, store for low-risk births

X

 

Collection based on need (eg, history of drug exposure, maternal urine screen results, NAS symptoms/diagnosis)

X

X

Tracking of specimen collection and handling process required

X

X

Fastest available time to result when positive results are expected

X

 

Traditional testing approach (screen with reflex to confirmation testing) preferred

 

X

Most sensitive and definitive testing for cannabis use

 

X

Most sensitive and definitive testing for heroin use

X

 

Preferred for the detection of the following drug(s): gabapentin, fentanyl, meperidine, propoxyphene, tramadol, tapentadol, phentermine, and/or zolpidem

X

 

Meconium specimen is limited or unavailable

X

 

Cord tissue specimen is limited or unavailable

 

X

ARUP Umbilical Cord Tissue Testing

Routine analysis by the ARUP drug detection panel includes qualitative detection by mass spectrometric methods for all compounds (eg, opioids, stimulants, sedative-hypnotics). Presence of metabolites improves confidence in results and lengthens detection window. Umbilical cord testing is thought to reflect maternal drug use during approximately the last trimester of a full-term birth. Tests to detect marijuana metabolite and ethyl glucuronide (alcohol metabolite) are available separately from the panel.

Additional Resources

Umbilical cord tissue collection instructions

Umbilical cord tissue collection video

Test Fact Sheets: ARUP Drug Detection Panel, Umbilical Cord Tissue (Qualitative) and Ethyl Glucuronide, Umbilical Cord Tissue, Qualitative

ARUP Meconium Testing

Routine analysis by the ARUP panel includes a qualitative screen for nine drug classes; specimens testing positive for one or more drugs are reflexed to confirmatory testing by highly sensitive and specific mass spectrometric methods. Directed (confirmation only) tests are available when only one drug class is of clinical interest or when quantity of meconium available for testing is very small (eg, <1 g).

The panel is the preferred meconium test to detect and document maternal drug use during pregnancy (approximately the last trimester of a full-term birth). Targeted single drug class testing is appropriate if only a particular drug class or classes are of clinical interest, or when quantity of meconium available for testing is very small (eg, <1 g).

Evaluation and Interpretation of Results

Drugs administered to the mother during labor and delivery may be detected in meconium or umbilical cord tissue. Drugs administered to the newborn after birth may be detected in meconium if the meconium is collected after drug administration.

Negative results do not exclude the possibility that the mother used drugs during pregnancy; only the drugs targeted by the testing can be detected. Maternal history and urine testing may also identify a possible infant drug exposure and should be used in combination with other laboratory results, as well as the infant’s clinical presentation, to diagnose a drug exposure.

Specimen variations can contribute to false-negative results. When definitive analytical methods (eg, liquid chromatography-tandem mass spectrometry [LC-MS/MS], gas chromatography-mass spectrometry [GC-MS]) are used, false-positive results are extremely unlikely.

Refer to the Drug Testing topic for test result interpretation organized by drug class.

Additional Resources

Opioid Metabolic Pathway

Thumbnail for Opioid metabolic pathway graphic

Benzodiazepine Metabolic Pathway

Thumbnmail for Benzodiazepine metabolic pathway graphic

ARUP Drug Cut-Off Limits for Meconium and Umbilical Cord Tissue

Thumbnail for link to ARUP Drug Cut-Off Limits for Meconium and Umbilical Cord pdf

Includes drug classes/metabolites, common trade/street names, and lowest concentration reported

ARUP Lab Tests

Umbilical Cord Tissue Testing

Detect and document maternal drug use during approximately the last trimester of a full-term pregnancy

Primary drugs detected:

  • Opioids: heroin metabolite (6-acetylmorphine), morphine, codeine, oxycodone, oxymorphone, hydrocodone, fentanyl, tramadol, tapentadol, propoxyphene, meperidine, buprenorphine, methadone
  • Stimulants: cocaine, methamphetamine/amphetamine, methylenedioxymethamphetamine (MDMA-Ecstasy), phentermine
  • Sedative-hypnotics: benzodiazepines, barbiturates
  • Other drugs: gabapentin, zolpidem, phencyclidine (PCP)

Additional technical informationTest Fact Sheet: Drug Detection Panel, Umbilical Cord Tissue (Qualitative)

Detect in utero exposure to cannabis (marijuana) in neonates consistent with maternal use during approximately the last trimester of pregnancy

Detects cannabinoid (THC)

Detect and document maternal use of ethanol during approximately the last trimester of pregnancy

Meconium Testing

Preferred meconium test to detect and document maternal drug use during approximately the last trimester of pregnancy

Panel detects ​opioids, stimulants, sedative-hypnotics, PCP, cannabinoids (11-nor-9-carboxy-THC)

Several drug metabolites are also included to increase likelihood of detection and increase confidence in results

See targeted drug class testing below for all components

Confirmation/Quantitation Meconium Tests

Use for infant drug testing when specific drug exposure is of clinical interest or when quantity of meconium available for testing is very small (eg, <1 g).

Test detects amphetamine, methamphetamine, MDMA-Ecstasy, methylenedioxyethylamphetamine (MDEA-Eve), methylenedioxyamphetamine (MDA)

Test detects alprazolam, alpha-hydroxyalprazolam, clonazepam, 7-aminoclonazepam, diazepam, chlordiazepoxide, lorazepam, midazolam, alpha-hydroxymidazolam, nordiazepam, oxazepam, temazepam

Test detects butalbital, phenobarbital

Test detects buprenorphine, norbuprenorphine

Test detects 9-carboxy-THC

Test detects cocaine, benzoylecgonine, M-hydroxybenzoylecgonine (qualitative only), cocaethylene

Test detects methadone and metabolite (EDDP)

Test detects codeine, morphine, 6-acetylmorphine, hydrocodone, hydromorphone, oxycodone, oxymorphone

Test detects PCP

Medical Experts

Contributor

McMillin

Gwendolyn A. McMillin, PhD
Professor of Clinical Pathology, University of Utah
Scientific Director, Mass Spectrometry Platform; Medical Director, Clinical Toxicology and Pharmacogenomics, ARUP Laboratories

References

Resources from the ARUP Institute for Clinical and Experimental Pathology®