What is Neonatal Abstinence Syndrome (NAS)? NAS is a drug withdrawal syndrome that occurs primarily after antenatal exposure to opioids or nonopioid drugs (including cocaine, benzodiazepines, and amphetamines).
Opioid medications are often prescribed for pain and are highly addictive during pregnancy. Opioids (including heroin, morphine, methadone, buprenorphine, and prescription opioid medications) are small compounds that cross the blood-brain and placental barrier to expose the vulnerable developing central nervous system of the fetus.1 After delivery, when intrauterine opioid exposure has stopped, the neonate can experience symptoms of NAS within 72 hours to several days and weeks, such as central nervous system (CNS) hyperirritability, gastrointestinal (GI) dysfunction, excessive crying, respiratory distress, poor sucks, hypotonia or hypertonia, fever, poor sleep patterns, and growth difficulties.1 Symptomatic severity can vary and is dependent on the type of illicit drug(s) consumed by the pregnant women and the extent of the intrauterine exposure.2
NAS withdrawal and intensity factors
Infants born at term and with good birth weight, polydrug-exposed neonate, and infants with delayed drug metabolism are at higher risk of severe and prolonged NAS withdrawal.3 Moreover, other factors increasing the intensity of NAS are maternal smoking, methadone use, and male gender.
Infants born with opioid toxicity are at risk of impaired neurodevelopment.2 During pregnancy, the use of opioids causes 60% to 90% of neonates with NAS, which reached ~13,000 infants per year in the United States.
NAS hospital care and treatment
Neonates with NAS stay in the hospital for an average of 16.4 days compared with 3.3 days for those without NAS. There is no effective treatment for NAS at this moment. Breast milk intake reduces NAS’s severity significantly.4 Infants fed predominantly with breast milk have reduced NAS scores, delayed onset of withdrawal, decreased need for medication, and shorter hospitalization than formula-fed infants.5 Donor breast milk also reduced the severity of GI distress in infants with NAS.6 However, the major breast milk components that lessen the NAS symptoms are still unknown.
NAS breast milk impacts
Abdel-Latif et al. investigated the effects of breast milk feeding on the severity of NAS in a population of infants of drug-dependent mothers at risk of NAS. Among the groups, 105 infants were fed cow formula and 85 infants were fed breast milk (58 were breastfed and 27 given expressed breast milk by bottle or gavage tube feeds) and were compared for the severity of NAS. Infants fed with breast milk significantly reduced mean NAS score, delayed onset of withdrawal, decreased need for medication, and shorter hospitalization than infants fed cow formula.5 This study suggests that breast milk intake reduces the severity of NAS regardless of the gestational age or the type of drug exposure.
In another study, Alexander et al. found that donor breast milk may decrease severe gastrointestinal distress (GI) in infants with NAS.6 Women with perinatal drug exposure were recruited when they could not provide their breast milk due to drug use six weeks before delivery. Infants were exclusively fed donor breast milk (provided by Medolac Laboratories, A Public Benefit Corporation) for 2 weeks. The proportion of infants with GI sub-cores greater than 2 (for significant disturbance and more intense GI distress) was higher in infants fed cow formula than in the infants fed donor breast milk. These findings suggest that donor breast milk reduced the severity of GI distress in infants with NAS during the withdrawal period after perinatal opioid exposure.
Overall, previous studies suggest that breast milk intake plays a role in reducing NAS symptoms. Non-pharmacological strategies, such as breast milk, can be valuable and effective adjunctive therapies for lactating women with drugs abuses or mother-infant duad undergoing medication-assisted treatment. Nutritional or immunological components in breast milk that reduce the severity of NAS and enhance neurodevelopment are not yet identified. A more extensive study is needed to investigate which breast milk components are responsible for reducing the severity of NAS.
1. Busch DW. Clinical management of the breast-feeding mother–infant dyad in recovery from opioid dependence. Journal of Addictions Nursing 2016;27:68-77.
2. Hudak ML, Tan RC. Neonatal drug withdrawal. Pediatrics 2012;129:e540-60.
3. Kocherlakota P. Neonatal abstinence syndrome. Pediatrics 2014;134:e547-e61.
4. Jansson LM. ABM clinical protocol# 21: Guidelines for breastfeeding and the drug-dependent woman. Breastfeeding Medicine 2009;4(4):2009 Dec 1;4(4):225-8.
5. Abdel-Latif ME, Pinner J, Clews S, Cooke F, Lui K, Oei J. Effects of breast milk on the severity and outcome of neonatal abstinence syndrome among infants of drug-dependent mothers. Pediatrics 2006;117(6):e1163-0.
6. Alexander C, Radmacher P, Devlin L. Donor human milk may decrease severe gastrointestinal distress in infants with neonatal abstinence syndrome. Journal of Pregnancy Neonatal Medicine 2017;1(1):11-5.
About the Author
Dr. Veronique Demers-Mathieu is the Senior Research Scientist in the department of Neonatal Immunology and Microbiology at Medolac Laboratories. She did 3-years of postdoctoral training in Neonatal Nutrition under Dr. Dallas at Oregon State University and earned her Ph.D. in Food Microbiology at Laval University. Her expertise focuses on the immune components (including antibodies, immune cells, cytokines, and bioactive proteins) from human milk that protect infants against infectious diseases.