Impact of timing of methadone initiation on perinatal outcomes following delivery among pregnant women on methadone maintenance therapy in Ontario. (30th October 2018)

• Record Type: Journal Article
• Authors: Guan, Qi; Sproule, Beth A.; Vigod, Simone N.; Cadarette, Suzanne M.; Greaves, Simon; Martins, Diana; Gomes, Tara
• Is Part Of: Addiction. Volume 114:Number 2(2019)
• Page Start: 268
• Page End: 277
• Publication Date: 2018-10-30
• Subjects: Addiction -- methadone maintenance therapy -- opioid -- opioid agonist therapy -- opioid use disorder -- pregnancy; Alcoholism -- Periodicals; Drug addiction -- Periodicals; 616.86
• DOI: 10.1111/add.14453
• Languages: English
• ISSNs: 0965-2140

Abstract

Abstract: Background and Aims: Methadone maintenance therapy (MMT) is associated with improved outcomes for children exposed to maternal opioid dependence in utero . We examined Ontario's population of pregnant women on MMT and determined the impact of timing of MMT initiation on perinatal outcomes. Design: Cohort study. Setting: Ontario, Canada. Participants: Women eligible for public drug benefits and on MMT during pregnancy between 2005 and 2015. Measurements: We stratified women based on their timing of MMT initiation: (1) stabilized prior to conception, (2) newly initiated prior to conception, (3) initiation in trimester 1, (4) initiation in trimester 2 or (5) initiation in trimester 3. The primary outcomes in the multivariable logistic regression analysis were key perinatal health indicators: small for gestational age, preterm birth, congenital anomalies, severe maternal morbidity, caesarean section and induced labor. Secondary outcomes were specific to maternal opioid dependence: neonatal abstinence syndrome (NAS), admission to a neonatal intensive care unit (NICU), NAS treatment, removal from mother's custody at hospital discharge and neonatal death. Findings: Among 1842 women on MMT during pregnancy, 87.6% ( n = 1614) initiated MMT before conception. Almost a quarter of their infants (22.2%; n = 408) were born small for gestational age, 17.5% ( n = 323) were preterm and 5.9% ( n = 109) were born with a congenital anomaly. The odds of primary outcomes occurring did not differ based on timing of methadone initiation; however, infants of mothers who initiated methadone during pregnancy had up to a fourfold increase in the odds of social services removal at the hospital [adjusted odds ratio (aOR) range = 3.70–4.19] compared with those whose mothers were stabilized on MMT prior to conception. Conclusions: Later initiation of methadone maintenance therapy among pregnant women in Ontario, Canada has not been found to be clearly related to most key perinatal adverse health outcomes.