Prescription drug use among pregnant women in opioid Maintenance Treatment

Mechanistic insights into the efficacy of memantine in treating certain drug addictions

The deleterious effects of the drug addiction epidemic are compounded by treatment strategies that are only marginally efficacious. Memantine is a unique glutamatergic medication with proven ability to attenuate drug addiction in preclinical models. However, clinical translational studies are inconsistent. In this review, we summarize preclinical evidences and clinical trials that investigated the efficacy of memantine in treating patients with alcohol, opiate, cocaine, and nicotine use disorders and discuss the results from a mechanistic point of view. Memantine has shown efficacy in reducing alcohol and opiate craving, consumption, and withdrawal severity. However, in cocaine and nicotine use disorders, memantine did not have significant effect on cravings or consumption. Additionally, memantine was associated with increased subjective effects of alcohol, cocaine, and nicotine. We discuss possible mechanisms behind this variability. Since memantine transiently blocks NMDA receptors and protects neurons from overstimulation by excessive synaptic glutamate, its efficacy should be observed in drug phases that cause hyperglutamatergic states, while hypoglutamatergic drug use states would not resolve with blocking NMDA receptors. Second, memantine pharmacokinetic studies have been done in rodents and healthy volunteers, but not in patients with substance use disorder. Memantine, opiates, cocaine, and nicotine share the same transporter family at the blood brain barrier. This shared transport mechanism could impact brain concentrations of memantine and its effects. In conclusion, memantine remains an intriguing compound in our pharmacopeia with controversial results in treating certain aspects of drug addiction. Further studies are needed to understand the clinical and biological correlates of its efficacy.

"They're not doing enough.": women's experiences with opioids and naloxone in Toronto

BACKGROUND

Amid increasing opioid overdose deaths in Canada since 2010 and a changing naloxone access landscape, there is a need for up-to-date research on Canadian women's experiences with opioids. Studies on Canadian take-home naloxone programs are promising, but research beyond these programs is limited. Our study is the first to focus on women's experiences and perspectives on the opioid crisis in Ontario, Canada's most populous province, since the opioid crisis began in 2010.

OBJECTIVE

Our objective was to address research knowledge gaps involving Canadian women with criminal justice involvement who use opioids, and identify flaws in current policies, responses, and practices. While the opioid overdose crisis persists, this lack of research inhibits our ability to determine whether overdose prevention efforts, especially involving naloxone, are meeting their needs.

METHODS

We conducted semi-structured, qualitative interviews from January to April 2018 with 10 women with experience of opioid use. They were recruited through the study's community partner in Toronto. Participants provided demographic information, experiences with opioids and naloxone, and their perceptions of the Canadian government's responses to the opioid crisis. Interviews were transcribed verbatim and inductive thematic analysis was conducted to determine major themes within the data.

RESULTS

Thematic analysis identified seven major concerns despite significant differences in participant life and opioid use experiences. Participants who had used illicit opioids since naloxone became available over-the-counter in 2016 were much more knowledgeable about naloxone than participants who had only used opioids prior to 2016. The portability, dosage form, and effects of naloxone are important considerations for women who use opioids. Social alienation, violence, and isolation affect the wellbeing of women who use opioids. The Canadian government's response to the opioid crisis was perceived as inadequate. Participants demonstrated differing needs and views on ideal harm reduction approaches, despite facing similar structural issues surrounding stigma, addiction management, and housing.

CONCLUSIONS

Participants experienced with naloxone use found it to be useful in preventing fatal overdose, however many of their needs with regards to physical, mental, and social health, housing, harm reduction, and access to opioid treatment remained unmet.

Association of Maternal Opioid Use in Pregnancy With Adverse Perinatal Outcomes in Ontario, Canada, From 2012 to 2018

IMPORTANCE

A recent epidemic of opioid abuse has been described in many communities, although population-based data on trends in use in pregnancy and perinatal outcomes after in utero exposure remain limited.

OBJECTIVE

To assess trends in prenatal opioid use and the potential association between prenatal opioid use and preterm birth and adverse perinatal outcomes.

DESIGN, SETTING, AND PARTICIPANTS

This population-based retrospective cohort study covered live births and stillbirths among adolescents and women 15 years and older from April 1, 2012, to March 31, 2018, in Ontario, Canada. Data were analyzed from July 29 to October 15, 2019.

EXPOSURES

Any opioid use in pregnancy, ascertained through self-reporting and routine prenatal care.

MAIN OUTCOME AND MEASURES

The primary outcome was preterm birth before a gestational age of 37 weeks. Separate indicators for birth occurring at gestational ages of 34 to 36 weeks (plus 6 to 7 days; late preterm), 32 to 33 weeks (plus 6 to 7 days), 28 to 31 weeks (plus 6 to 7 days), and less than 28 weeks (very preterm birth). Secondary outcomes included small for gestational age, stillbirth, transfer to neonatal intensive care, and 5-minute Apgar score. Coarsened exact matching techniques and Poisson regression models were used to estimate the risk difference and relative risk (RR) of outcomes associated with cannabis exposure to control for confounding.

RESULTS

Among 710 911 women included in the analytic sample (mean [SD] age, 30.4 [5.3] years), 8059 used opioids (1.1%), with prevalence decreasing from 1.31% (95% CI, 1.25%-1.38%) in fiscal year 2012-2013 to 1.05% (95% CI, 0.99%-1.11%) in fiscal year 2017-2018 (P < .001 for trend). Use was highest among women in the lowest quintile of area-level income (2.36% vs 0.56% in the highest quintile; RR, 3.86; 95% CI, 3.58-4.15) and did not decrease over time in this group (from 2.63% [95% CI, 2.41%-2.87%] in 2012-2013 to 2.35% [95% CI, 2.14%-2.58%] in 2017-2018; P = .23 for trend). The crude rate of preterm birth at a gestational age of less than 37 weeks was 14.0% (n = 1127) among women with reported use in pregnancy and 6.0% (n = 42 226) among women who did not use opioids in the unmatched cohort. The adjusted RR for preterm birth before a gestational age of 37 weeks was 1.63 (95% CI, 1.52-1.75) among opioid users compared with nonusers and 1.77 (95% CI, 1.35-2.31) for preterm birth before 32 weeks. Among newborns, risk for neonatal intensive care was 40.5% with perinatal exposure to opioids compared with 13.9% in unexposed infants (RR, 2.91; 95% CI, 2.80-3.03).

CONCLUSIONS AND RELEVANCE

Rates of opioid use in pregnancy have declined in recent years, although use remains significantly higher among lower-income women. In this large population-based cohort, opioid use in pregnancy was associated with an increased risk of preterm birth and admission to a neonatal intensive care unit.

Prenatal exposure to opioid maintenance treatment and neonatal outcomes: Nationwide registry studies from the Czech Republic and Norway

There is lack of knowledge about the safety of treatment with methadone and buprenorphine as part of opioid maintenance treatment (OMT) during pregnancy. The purpose of this study was to examine neonatal outcomes concerning the use of OMT during pregnancy. We used nationwide registry linkages from the Czech Republic (2000-2014) and Norway (2004-2013). We compared prenatally OMT-exposed newborns with (a) newborns of women hospitalized with opioid use disorder during pregnancy in the Czech sample and (b) newborns with neonatal abstinence syndrome (NAS) in Norway. We performed multivariate linear and binary logistic regression exploring the associations between OMT and neonatal outcomes (growth parameters, gestational age, fetal death, small for gestational age, Apgar score, and NAS). Regression coefficients (b) and odds ratios (ORs) were estimated. The cohorts consisted of 333 Czech, and 235 Norwegian OMT-exposed newborns, and 106 and 294 newborns in the comparison groups, respectively. In both countries, the neonatal growth parameters were similar in the OMT and the comparison groups. In Norway, OMT exposure prolonged gestational age (adjusted b = 0.96 weeks, 95% confidence interval [CI] =0.39-1.53) while the odds of preterm birth and Apgar score at 5 minutes were lower than in the comparison group (adjusted OR = 0.35, 0.16-0.75 and aOR = 0.21, 0.06-0.78, respectively). Newborns of women in OMT had similar growth parameters as newborns of women with opioid use disorders who were not in OMT during pregnancy. Overall, our findings do not suggest that OMT results in worse neonatal outcomes.

Epidemiology of perinatal substance use: Exploring trends in maternal substance use

Over the last two decades, the prevalence of substance use among women of childbearing age has risen dramatically in the United States making substance use during pregnancy a significant public health concern. This article offers a general overview of the epidemiology of perinatal substance use focusing primarily on the United States but when available international trends will be presented as well.

Neonatal outcomes after fetal exposure to methadone and buprenorphine: national registry studies from the Czech Republic and Norway

BACKGROUND AND AIMS

Opioid maintenance treatment (OMT) is recommended to opioid-dependent females during pregnancy. However, it is not clear which medication should be preferred. We aimed to compare neonatal outcomes after prenatal exposure to methadone (M) and buprenorphine (B) in two European countries.

DESIGN

Nation-wide register-based cohort study using personalized IDs assigned to all citizens for data linkage.

SETTING

The Czech Republic (2000-14) and Norway (2004-13). [Correction added after online publication on 26 April 2018: The Czech Republic (2000-04) corrected to (2000-14).] PARTICIPANTS: Opioid-dependent pregnant Czech (n = 333) and Norwegian (n = 235) women in OMT who received either B or M during pregnancy and their newborns.

MEASUREMENTS

We linked data from health registries to identify the neonatal outcomes: gestational age, preterm birth, birth weight, length and head circumference, small for gestational age, miscarriages and stillbirth, neonatal abstinence syndrome (NAS) and Apgar score. We performed multivariate linear regression and binary logistic regression to explore the associations between M and B exposure and outcomes. Regression coefficient (β) and odds ratio (OR) were computed.

FINDINGS

Most neonatal outcomes were more favourable after exposure to B compared with M, but none of the differences was statistically significant. For instance, in the multivariate analysis, birth weight was β = 111.6 g [95% confidence interval (CI) = -10.5 to 233.6 and β = 83.1 g, 95% CI = -100.8 to 267.0] higher after B exposure in the Czech Republic and Norway, respectively. Adjusted OR of NAS for B compared with M was 0.94 (95% CI = 0.46-1.92) in the Norwegian cohort.

CONCLUSIONS

Two national cohorts of women receiving opioid maintenance treatment during pregnancy showed small but not statistically significant differences in neonatal outcomes in favour of buprenorphine compared with methadone.

A Unique Opportunity to Study Short and Long Term Consequences in Children Prenatally Exposed to Illicit Drugs and Opioid Maintenance Treatment Using Czech and Scandinavian Registers

Licit and illicit drug use in pregnant women constitutes a long lasting and serious problem worldwide. Information on long-term effects of maternal drug use on the child is limited. Nationwide registers provide a great potential to study short and long-term consequences for children exposed to licit and illicit drugs during pregnancy. We discuss this potential, with a special emphasis on exposure to methamphetamine, heroin and prescription drugs used for opioid maintenance treatment (OMT). We also discuss the advantages of register data and of merging such data from different regions. The Czech and Scandinavian registers are largely comparable and provide great opportunities to conduct innovative research. For instance, using Czech and Scandinavian cohorts we can compare groups with similar characteristics, such as mothers in OMT and mothers addicted to other drugs while also controlling for important confounding factors such as health and socio-economic status.

Maternal Use of Opioids During Pregnancy and Congenital Malformations: A Systematic Review

CONTEXT

Opioid use and abuse have increased dramatically in recent years, particularly among women.

OBJECTIVES

We conducted a systematic review to evaluate the association between prenatal opioid use and congenital malformations.

DATA SOURCES

We searched Medline and Embase for studies published from 1946 to 2016 and reviewed reference lists to identify additional relevant studies.

STUDY SELECTION

We included studies that were full-text journal articles and reported the results of original epidemiologic research on prenatal opioid exposure and congenital malformations. We assessed study eligibility in multiple phases using a standardized, duplicate review process.

DATA EXTRACTION

Data on study characteristics, opioid exposure, timing of exposure during pregnancy, congenital malformations (collectively or as individual subtypes), length of follow-up, and main findings were extracted from eligible studies.

RESULTS

Of the 68 studies that met our inclusion criteria, 46 had an unexposed comparison group; of those, 30 performed statistical tests to measure associations between maternal opioid use during pregnancy and congenital malformations. Seventeen of these (10 of 12 case-control and 7 of 18 cohort studies) documented statistically significant positive associations. Among the case-control studies, associations with oral clefts and ventricular septal defects/atrial septal defects were the most frequently reported specific malformations. Among the cohort studies, clubfoot was the most frequently reported specific malformation.

LIMITATIONS

Variabilities in study design, poor study quality, and weaknesses with outcome and exposure measurement.

CONCLUSIONS

Uncertainty remains regarding the teratogenicity of opioids; a careful assessment of risks and benefits is warranted when considering opioid treatment for women of reproductive age.

Patterns of polydrug use among pregnant substance abusers

Aim

Studies of drug use during pregnancy have generally focused on individual substances or specific combinations of drugs. The aim of this article is to increase our knowledge about polydrug use and pregnancy in a Nordic context by describing the sociodemographic characteristics of a clinical population of pregnant women with severe substance use, examining the scope and type of polydrug use and analysing factors associated with concurrent use of many, as opposed to a few, drugs.

Method

A cross-sectional study of pregnant women on admission to compulsory care for substance abuse in Sweden between 2000 and 2009 (n = 119 women, representing 128 pregnancies). Data were retrieved from administrative registers and client records. Univariate links between demographic, social, obstetrical, treatment history variables and polydrug use were examined. Binary logistic regression was used to analyse the association between explanatory variables and polydrug use.

Results

The average number of drugs being used concurrently was 2.65, and injection drug use was recorded in 73% of the pregnancies. Opiates and amphetamines were the most common primary drugs, followed by alcohol. The likelihood of polydrug use increased with first trimester pregnancy, planned (as opposed to emergency) committals, as well as the combination of partner substance abuse and injection drug use.

Conclusions

Polydrug use was widespread among pregnant substance abusers. Policies, interventions and research often focus on individual drugs separately, but for clinical populations in particular there is a need to address drug use broadly, including a systematic recording of smoking habits. This also entails awarding more attention to those not eligible for established interventions, such as opiate maintenance treatment, and giving more consideration to a variety of life circumstances, such as partner drug use.

Evaluation of the vaginal flora in pregnant women receiving opioid maintenance therapy: a matched case-control study

Background

Vaginal infections are a risk factor for preterm delivery. In this study, we sought to evaluate the vaginal flora of pregnant women receiving opioid maintenance therapy (OMT) in comparison to non-dependent, non-maintained controls.

Methods

A total of 3763 women with singleton pregnancies who underwent routine screening for asymptomatic vaginal infections between 10 + 0 and 16 + 0 gestational weeks were examined. Vaginal smears were Gram-stained, and microscopically evaluated for bacterial vaginosis, candidiasis, and trichomoniasis. In a retrospective manner, data of 132 women receiving OMT (cases) were matched for age, ethnicity, parity, education, previous preterm delivery, and smoking status to the data of 3631 controls. The vaginal flora at antenatal screening served as the primary outcome measure. Secondary outcome measures were gestational age and birth weight.

Results

In the OMT group, 62/132 (47 %) pregnant women received methadone, 39/132 (29.5 %) buprenorphine, and 31/132 (23.5 %) slow-release oral morphine. Normal or intermediate flora was found in 72/132 OMT women (54.5 %) and 2865/3631 controls [78.9 %; OR 0.49 (95 % CI, 0.33–0.71); p < 0.001]. Candidiasis occurred more frequently in OMT women than in controls [OR 2.11 (95 % CI, 1.26–3.27); p < 0.001]. Findings were inconclusive regarding bacterial vaginosis (± candidiasis) and trichomoniasis. Compared to infants of the control group, those of women with OMT had a lower mean birth weight [MD −165.3 g (95 % CI, −283.6 to −46.9); p = 0.006].

Conclusions

Pregnant women with OMT are at risk for asymptomatic vaginal infections. As recurrent candidiasis is associated with preterm delivery, the vulnerability of this patient population should lead to consequent antenatal infection screening at early gestation.

Electronic supplementary material

The online version of this article (doi:10.1186/s12884-016-1003-z) contains supplementary material, which is available to authorized users.

Epidemiological Evidence for a Decreasing Incidence of Neonatal Abstinence Syndrome, 2000-11

BACKGROUND

This study analyses the incidence of Neonatal Abstinence Syndrome (NAS) in a large geographically defined population in Australia.

METHOD

Database linkage analysis of all births between 2000 and 2011 in New South Wales (NSW), Australia. The diagnosis of NAS was derived from hospital coding P96.1, 'Neonatal withdrawal symptoms from maternal use of drugs of addiction'. Temporal trends were studied by comparing epoch 1 (2000-05) with epoch 2 (2006-11). The relationship with changes in maternal factors was further analysed.

RESULTS

The NAS was coded in 3842 of 1 022 263 live born infants (0.38%). NAS incidence peaked at 5.07 per 1000 live births in 2002, decreasing to 3.18 in 2011 and was negatively correlated with maternal age (r = -0.7). The rate of NAS in epoch 2 (3.4 per 1000 births, 95% CI 3.28, 3.58) was significantly lower than in epoch 1 (4.1 per 1000 births, 95% CI 3.96, 4.33). Epoch 2 mothers were significantly older (mean 29.8 years vs. 28.3 years), less likely to be multiparous (OR 0.7, 95% CI 0.6, 0.9) or smoke (OR 0.4, 95% CI 0.4, 0.5). They were more likely to engage in antenatal care earlier (mean first visit: 14.1 vs. 18.9 weeks). Most infants (~80%) were born at term (>37 weeks gestation).

CONCLUSION

The incidence of NAS as a discharge diagnosis has decreased in our population since 2002. Mothers are also older and engaging earlier in prenatal care. Whether these changes alter NAS presentation and diagnosis or whether pregnant women are using drugs that do not cause typical NAS (e.g. amphetamines) is uncertain and requires further study.

Clinical correlates of prescription opioid analgesic use in pregnancy

A 2012 committee opinion from the American College of Obstetricians and Gynecologists highlights the considerable increase in opioid addiction in recent years, yet little is known about clinical correlates of prescribed opioids among pregnant women. This study examines clinical and demographic factors associated with the use of opioid analgesics in pregnancy. Data were derived from a prospective cohort study of pregnant women. Participants were administered the Composite International Diagnostic Interview to identify depressive and anxiety disorders and data on medication use were gathered at three assessment points and classified according to the Anatomical Therapeutic Chemical Code (ATC) classification system ATC group N02A. Participants included 2,748 English or Spanish speaking pregnant women. Six percent (n = 165) of women used opioid analgesics at any point in pregnancy. More pregnant women using opioids met diagnostic criteria for major depressive disorder (16 vs. 8 % for non users), generalized anxiety disorder (18 vs. 9 % for non users), post-traumatic stress disorder (11 vs. 4 % for non users) and panic disorder (6 vs. 4 % for non users). Women who reported opioid use were also significantly more likely than non users to report using illicit drugs and almost three times as likely to report smoking cigarettes in the second or third trimester of pregnancy (4 and 23 %, respectively) as compared to non-opioid users (0.5 and 8 %). The use of opioids in pregnancy was associated with higher levels of psychiatric comorbidity and use of other substances as compared to non-opioid users.

Ethical aspects of registry-based research in the Nordic countries

National health care registries in the Nordic countries share many attributes, but different legal and ethical frameworks represent a challenge to promoting effective joint research. Internationally, there is a lack of knowledge about how ethical matters are considered in Nordic registry-based research, and a lack of knowledge about how Nordic ethics committees operate and what is needed to obtain an approval. In this paper, we review ethical aspects of registry-based research, the legal framework, the role of ethics review boards in the Nordic countries, and the structure of the ethics application. We discuss the role of informed consent in registry-based research and how to safeguard the integrity of study participants, including vulnerable subjects and children. Our review also provides information on the different government agencies that contribute registry-based data, and a list of the major health registries in Denmark, Finland, Iceland, Norway, and Sweden. Both ethical values and conditions for registry-based research are similar in the Nordic countries. While Denmark, Finland, Iceland, Norway, and Sweden have chosen different legal frameworks, these differences can be resolved through mutual recognition of ethical applications and by harmonizing the different systems, likely leading to increased collaboration and enlarged studies.

Harm to Others from Substance Use and Abuse: The Underused Potential in Nationwide Registers

This article considers the potential in using nationwide registers to study harm to others from substance use and abuse. The advantages of using registry data include the opportunity to include the data on the entire population nationwide and continuously updated longitudinal datasets; they allow for studying small subpopulations and have little missing data. Personal identification numbers and family numbers enable linkage of data from different registers. Such datasets can include extensive information on individual and family levels. In this article, we provide an introduction to nationwide registers and explain how they can be applied to investigate two types of third-party harms: harm to children and harm to partners/spouses from substance use and abuse in parents and partners/spouses. Finally, we discuss challenges, benefits, and ethical considerations regarding the use of such data.

Genetic determinants of fetal opiate exposure and risk of neonatal abstinence syndrome: Knowledge deficits and prospects for future research

Opiate-dependent pregnant women receive opiate maintenance medications to prevent illicit use and withdrawal. Fetal opiate exposure causes central nervous system (CNS) alterations which manifest as postnatal physical withdrawal. The extensive variability in the Neonatal Abstinence Syndrome phenotype remains unexplained and may be related to variability in fetal exposure and response. Improved understanding of functionally significant genetic variants in pathways influencing placental opiate transfer and fetal response can lead to personalized maternal therapy and optimized neonatal outcomes.

Benzodiazepine use among mothers of small children: a register-based cohort study

AIMS

To compare benzodiazepine (BZD) purchases in different groups of mothers of small children.

DESIGN

Prospective population-based cohort study based on the Finnish social and health care registers.

SETTING

Finnish women of child-bearing age.

PARTICIPANTS

All women who gave birth in 2002 in Finland (n = 54 519).

MEASUREMENTS

Latent class analysis (LCA) was used to create a typology of mothers according to their substance abuse status, psychiatric disorders and socio-demographic characteristics. The mothers were followed-up yearly for purchases of benzodiazepines, starting 4 years before the child's birth and continuing up to the child's 7th birthday. BZD purchases in different mother groups were compared using negative binomial hurdle models.

FINDINGS

The five mother types identified by LCA were mothers with substance abuse (1%), mothers with psychiatric disorders (1%), mothers with a risk of social marginalization (11%), mothers with minor social problems (18%) and mothers with no identified problems (69%; the comparison group). Mothers with substance abuse problems had the highest odds of purchasing BZDs [odds ratio OR = 27.5, 95%CI = 22.9-33.0; RR = 20.2, 95%CI = 14.9-27.3. The change in time was similar in all groups: the probability of purchasing and the number of purchases were lowest during pregnancy and the year of the child's birth.

CONCLUSIONS

In Finland, among mothers of young children, prevalence of benzodiazepine use is reduced during pregnancy and the child's first year, and then increases as the child grows older. Mothers with substance abuse and psychiatric disorders are at particularly high risk of benzodiazepine use.

Endogenous opiates and behavior: 2013

This paper is the thirty-sixth consecutive installment of the annual review of research concerning the endogenous opioid system. It summarizes papers published during 2013 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior, and the roles of these opioid peptides and receptors in pain and analgesia; stress and social status; tolerance and dependence; learning and memory; eating and drinking; alcohol and drugs of abuse; sexual activity and hormones, pregnancy, development and endocrinology; mental illness and mood; seizures and neurologic disorders; electrical-related activity and neurophysiology; general activity and locomotion; gastrointestinal, renal and hepatic functions; cardiovascular responses; respiration and thermoregulation; and immunological responses.

Breastfeeding reduces the need for withdrawal treatment in opioid-exposed infants

AIM

To examine the rate and duration of breastfeeding in a cohort of women in opioid maintenance treatment (OMT) in Norway, as well as the effect of breastfeeding on the incidence and duration of neonatal abstinence syndrome (NAS).

METHODS

A national cohort of 124 women treated with either methadone or buprenorphine during pregnancy, and their neonates born between 1999 and 2009, was evaluated in three study parts. A standardized questionnaire was administered, and medical information from the hospitals and municipalities were collected to confirm self-reported data.

RESULTS

There were high initiation rates of breastfeeding (77%) for women in OMT, but also high rates of early cessation of breastfeeding. Breastfed neonates exposed to methadone prenatally had significantly lower incidence of NAS requiring pharmacotherapy (53% vs. 80%), and both the whole group of infants and the methadone-exposed neonates needed shorter pharmacological treatment of NAS (p < 0.05) than neonates who were not breastfed.

CONCLUSION

Breastfed neonates exposed to OMT medication prenatally, and methadone-exposed newborns in particular, have lower incidence of NAS and require shorter pharmacotherapy for NAS than infants who are not breastfed. The results add to the evidence regarding the benefits of breastfeeding for neonates prenatally exposed to OMT medications.