Extended-release versus oral buprenorphine as opioid maintenance treatment during pregnancy-maternal and neonatal outcomes.

OBJECTIVE: To get information on subcutaneous extended-release buprenorphine as opioid maintenance treatment during pregnancy, we compared it to orally administered buprenorphine and buprenorphine-naloxone treatments. We hypothesized that maternal and neonatal outcomes do not differ between the treatment groups. Study design In this population-based cohort study, 60 pregnant individuals receiving non-changed opioid maintenance treatment for opioid use disorder with a buprenorphine product from the time before conception to the time after delivery and their newborns were included. They were divided into three groups based on the pharmacotherapy with subcutaneous extended-release buprenorphine, sublingual buprenorphine, or buprenorphine-naloxone. Statistical analyses were conducted using Fischer's exact tests, ANOVA tests, and Kruskal-Wallis tests. All the statistical tests were two-tailed. RESULTS: The frequency of pregnancy or delivery complications did not significantly differ between the group receiving extended-release buprenorphine and the other groups. During pregnancy, 38 % of the women used illicit drugs concomitantly, with equal frequency in the extended-release buprenorphine group and the other groups. Of the neonates, 93 % were born full-term and 90 % got at least eight Apgar points in one minute age, without significant differences between the groups (p = 0.57). The need for pharmacotherapy for neonatal opioid withdrawal syndrome was the lowest in the extended-release buprenorphine group (25 %) and highest in the sublingual buprenorphine group (67 %). Still, the difference between the treatment groups did not reach statistical significance (p = 0.17). Among all neonates, the breastfed infants were less likely to receive pharmacotherapy for withdrawal symptoms than the formula-fed ones (p = 0.048). CONCLUSIONS: Extended-release buprenorphine with steady drug concentration seems to be a promising pharmacotherapy option during pregnancy for mothers. Maternal health during pregnancy may contribute to the well-being of newborns. Larger trials are urgently needed to confirm these results..

Intrauterine exposure to maternal opioid maintenance treatment and associated risk factors may impair child growth.

AIM: How maternal opioid maintenance treatment (OMT) affects children is under-researched. This population-based registry study investigated child growth and somatic health following intrauterine exposure to this treatment. METHODS: Children born between 1 March 2011 and 30 May 2021 to mothers who used buprenorphine, buprenorphine-naloxone, or methadone throughout their pregnancies were followed for 2 years at the Helsinki University Hospital, Finland. Appropriate statistical tests were used to compare the treatment groups. RESULTS: Of the 67 neonates, 52% were male, 96% were born full-term and 63% were treated for neonatal opioid withdrawal syndrome. Otherwise, the children were predominantly healthy, although relatively small: 22% were small for gestational age, the methadone group children being the smallest. Foetal exposure to maternal methadone treatment, illicit drugs, hepatitis C and smoking were associated with small for gestational age; the former two were also associated with later slower growth, especially head growth and weight gain (p < 0.001). However, 29% were overweight at 2 years. CONCLUSION: Using child growth as the outcome, we found that buprenorphine-naloxone and buprenorphine-monotherapy had equal effects as forms of maternal OMT. Exposure to multiple risk factors may harm foetal and subsequent growth. We recommend long-term follow-up of children exposed to maternal OMT.

Buprenorphine-naloxone, buprenorphine, and methadone throughout pregnancy in maternal opioid use disorder.

INTRODUCTION: Current WHO guidelines recommend using methadone or buprenorphine as maintenance treatments for maternal opioid use disorder. However, buprenorphine-naloxone, with a lower abuse risk than buprenorphine monotherapy or methadone, offers a potentially beneficial alternative, but scientific evidence on its effects on pregnancies, fetuses, and newborns is scarce. This paper compares the outcomes of the pregnancies, deliveries, and newborns of women on buprenorphine-naloxone, buprenorphine, or methadone maintenance treatments. According to the hypothesis, as a maintenance treatment, buprenorphine-naloxone does not have more adverse effects than buprenorphine, whereas methadone is more complicated. MATERIAL AND METHODS: In this population-based study, 172 pregnant women on medical-assisted treatments were followed-up at Helsinki University Women's Hospital (Finland). Women receiving the same opioid maintenance treatment from conception to delivery and their newborns were included. Consequently, 67 mother-child dyads met the final inclusion criteria. They were divided into three groups based on their opioid pharmacotherapy. The outcomes were compared among the groups and, where applicable, with the Finnish population. RESULTS: The buprenorphine-naloxone and buprenorphine groups showed similar outcomes and did not significantly differ from each other in terms of maternal health during pregnancies, deliveries, or newborns. Illicit drug use during the pregnancy was common in all groups, but in the methadone group it was most common (p = 0.001). Most neonates (96%) were born full-term with good Apgar scores. They were of relatively small birth size, with those in the methadone group tending to be the smallest. Of the neonates 63% needed pharmacological treatment for neonatal opioid withdrawal syndrome. The need was lower in the buprenorphine-based groups than in the methadone group (p = 0.029). CONCLUSIONS: Buprenorphine-naloxone seems to be as safe for pharmacotherapy for maternal opioid use disorder as buprenorphine monotherapy for both mother and newborn. Hence it could be a choice for oral opioid maintenance treatment during pregnancy, but larger studies are needed before changing the official recommendations. Women on methadone treatment carry multifactorial risks and require particularly cautious follow up. Furthermore, illicit drug use is common in all treatment groups and needs to be considered for all patients with opioid use disorder.