A Pilot Daily Diary Study of Changes in Stress and Cannabis Use Quantity Across the Menstrual Cycle

Menstrual cycle (MC) phase appears to influence changes in females’ addictive behaviours (e.g., drinking,cigarette smoking). Few studies have examined cannabis use across the MC. We examined phase-specific changes in stress and cannabis use quantity across the MC in daily cannabis users. We hypothesized there would be an increase in self-reported stress and cannabis quantity premenstrually and menstrually versus other MC phases. Data were obtained prospectively, using a 32-day daily diary, from 14 normally- cycling, community-recruited, female cannabis users (Age: M = 29.3 years old, SD = 4.9). Participants completed measures pertaining to their daily stress levels (the General Stress Scale) and the quantity of cannabis used daily. A priori planned comparison t-tests and non-parametric Wilcoxon rank tests revealed MC phase effects on stress levels and cannabis quantity, respectively. In partial support of stress-response dampening (SRD) model and self-medication theory (SMT) predictions, stress levels were higher in the premenstrual versus the ovulatory phase, and a higher quantity of cannabis was used premenstrually versus the follicular and ovulatory phases. Findings suggest stress levels and cannabis use quantity are MC phase-sensitive. Results are consistent with SRD model and SMT predictions, where females learn to increase the quantity of cannabis used premenstrually to dampen their heightened stress response and negative affect. Female cannabis users of reproductive age could be trained to employ alternative strategies to cope with elevated stress during the premenstrual phase to prevent increased cannabis use.