314: Is opioid maintenance therapy (OMT) associated with placentomegaly and placental dysmaturity?

To explore the effects of gestational OMT on placental development This is a retrospective cohort study of pregnant patients on OMT (buprenorphine or methadone) between January 2007 and December 2017. ICD codes were used to identify OMT patients. The control group consisted of random non-drug users matched for GA. Patients were excluded if they had gestational diabetes, multiple gestations, positive meconium toxicology results for substances other than methadone or buprenorphine and those without microscopic placental evaluation. Placental weight and histologic evaluation were obtained and compared among the groups. Data analysis was performed using one-way ANOVA with p-value <0.05 significant. 454 cases were reviewed; of which 109 met the inclusion criteria (66 patients were on methadone, 43 were on buprenorphine, and 40 were controls). Gestational age at birth and neonatal birth weight were significantly lower in the methadone group compared to the buprenorphine and control groups . The placenta to neonatal birth weight ratio was significantly higher in the methadone and buprenorphine groups compared to controls (p<0.01). There was no statistically significant difference between methadone and buprenorphine groups (mean ± standard deviation; methadone: 0.19 ± 0.03; buprenorphine: 0.18 ± 0.04; control: 0.15 ± 0.03).The rate ratio of placental dysmaturity (Figure 1) was significantly higher in the methadone and buprenorphine groups compared to control (rate ratio 3.8 and 3.7) Gestational OMT is associated with placentomegaly and placental dysmaturity compared to non- drug users. These findings are correlated with reduced surface area for oxygen diffusion, which may affect neonatal well-being. Further analysis is underway to evaluate the effects of placental dysmaturity on neonatal outcomes.View Large Image Figure ViewerDownload Hi-res image Download (PPT)