Neonatal outcomes after fetal exposure to methadone
and buprenorphine: national registry studies from the
Czech Republic and Norway
, Viktor Mravčík
, Svetlana Skurtveit
, Anders Engeland
Department of Addictology, First Faculty of Medicine, Charles University, Prague, Czech Republic,
National Monitoring Centre for Drugs and Addiction, Ofﬁce of the
Government of the Czech Republic, Prague, Czech Republic,
Norwegian institute of Public Health, Oslo, Norway,
Norwegian Centre for Addiction Research at the
University of Oslo, Oslo, Norway
and Department of Global Public Health and Primary Care, University of Bergen, Bergen, 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.
register-based cohort study using personalized IDs assigned to all citizens for data linkage.
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).]
Opioid-dependent pregnant Czech (n = 333) and Norwegian
(n = 235) women in OMT who received either B or M during pregnancy and their newborns.
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.
outcomes were more favourable after exposure to B compared with M, but none of the differences was statistically signif-
icant. For instance, in the multivariate analysis, birth weight was β =111.6g[95%conﬁdence interval (CI) = À10.5 to
233.6 and β = 83.1 g, 95% CI = À100.8 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.
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.
Keywords Buprenorphine, health registries, methadone, neonatal outcomes, opioid maintenance treatment,
Correspondence to: Blanka Nechanská, Charles University, First Faculty of Medicine, Department of Addictology, Apolinářská 4, 120 00 Prague 2, Czech
Republic. E-mail: email@example.com
Submitted 12 April 2017; initial review completed 7 June 2017; ﬁnal version accepted 5 February 2018
Pregnant women with opioid dependence, according to the
World Health Organization (WHO) guidelines for
identiﬁcation and management of substance use and
substance use disorders in pregnancy, should be advised to
continue or commence pharmacotherapy with either meth-
adone or buprenorphine [1,2]. Such pharmacotherapy
combined with psychosocial support is often called opioid
maintenance treatment (OMT). However, while WHO
strongly recommends OMT during pregnancy, the same
guidelines underscore that the quality of the evidence
behind this recommendation is, to date, very low.
The most used medications for OMT are methadone
(M), and buprenorphine (B), alone or in combination with
naloxone (BN). M and B are both long-acting opioid
agonists, but differ somewhat with respect to pharmaco-
logical properties . While the WHO guidelines
recommend M for pregnant opioid-dependent women,
national recommendations for this patient group might
© 2018 Society for the Study of Addiction Addiction, 113,1286–1294