Menstrual cyclicity of cannabis use: a longitudinal study using phase-aligned cycle time scaling (PACTS)

Despite rising rates of cannabis use and cannabis use disorder (CUD) among females, research on female-specific implicated factors remains limited. Emerging evidence suggests that substance use behavior may fluctuate across the menstrual cycle, particularly among individuals with premenstrual disorders (PMDs). However, findings for cannabis use are limited and inconsistent. The present study aimed to investigate menstrual cyclicity of cannabis use likelihood and quantity, and potential implicated factors.

Naturally cycling individuals with diagnosed or suspected PMDs were followed prospectively for 2-3 menstrual cycles. Participants completed daily rating of cannabis use and premenstrual symptom severity using the Daily Record of Severity of Problems (DRSP). The novel phase-aligned cycle time scaling (PACTS) method was used to generate a continuous, phase-aligned cycle-time variable anchored to both menses onset and ovulation, and associations were modeled using generalized additive mixed models.

Daily quantity of dried cannabis flower used showed menstrual cyclicity (p = 0.030), peaking before menses onset and around ovulation. Daily core affective symptoms of PMDs (p = 0.004), particularly emotional/rejection sensitivity (p = 0.004) and interpersonal conflicts/problems (p = 0.010), also moderated this cyclicity. Specifically, higher-than-usual daily symptom levels were associated with increased cannabis flower quantity used premenstrually, whereas lower-than-usual symptom levels were associated with decreased premenstrual cannabis use quantity.

The findings suggest that the quantity of dried cannabis flower used fluctuates meaningfully across the menstrual cycle and is shaped by daily affective symptoms of PMDs. If replicated, these findings highlight the importance of incorporating menstrual cycle timing and PMD symptoms into prevention and treatment strategies for cannabis use.