Prevention of postpartum methamphetamine use with micronized progesterone trial (PROMPT): A pilot randomized controlled trial.

OBJECTIVES: Methamphetamine use disorder (MUD) contributes to postpartum morbidity and mortality. Postpartum progesterone decline may destabilize γ-aminobutyric acid pathways, increasing craving and return to use. We assessed the feasibility and safety of micronized progesterone, generating efficacy estimates for preventing postpartum methamphetamine use. METHODS: We conducted a double-blind, randomized, placebo-controlled feasibility trial (November 2021-January 2024) at an academic center with a perinatal addiction clinic. Participants ≤ 12 weeks postpartum with ≥ 4 weeks of abstinence were randomized 1:1, stratified by opioid use disorder (OUD), to micronized progesterone 400mg (200mg twice daily) or identical placebo for 12 weeks. The primary outcome was feasibility, defined as achieving ≥ 80% of planned enrollment. Safety outcomes included adverse events (AEs) and serious adverse events (SAEs). Efficacy outcomes were return to methamphetamine use (weekly self-report and every two weeks urine toxicology) and methamphetamine craving. Analyses included intent-to-treat and per-protocol approaches, with loss to follow-up imputed as return to use. Craving trajectories were modeled using adjusted regression with interaction terms for medication for OUD (MOUD). RESULTS: Of 253 screened individuals, 43 were eligible and 34 were enrolled (91.8%; 18 progesterone, 16 placebo). Retention at 12 weeks was 88%. AE frequency was similar between groups (78% vs 81%; p > 0.05), and no maternal SAEs occurred. Four infant SAEs were deemed unrelated to treatment. Return to methamphetamine use did not differ between groups. Craving trajectories differed by MOUD type. CONCLUSIONS: Micronized progesterone was feasible and safe for postpartum individuals with MUD. MOUD-specific craving effects support evaluation in larger, multicenter efficacy trials. GOV REGISTRATION NUMBER: NCT05128071 NCT REGISTRATION: Prevention of postpartum methamphetamine use with micronized progesterone trial https://clinicaltrials.gov/study/NCT05128071.