The effect of the COVID-19 pandemic on substance use patterns and physiological dysregulation in pregnant and postpartum women

During the COVID-19 pandemic, pregnant and postpartum women faced increased psychological stress, which is often linked to shifts in substance use and autonomic nervous system (ANS) functioning. This study investigated how the pandemic influenced substance use patterns and physiological health in these populations. The researchers utilized a prospective cohort of 71 participants, tracking substance use through baseline surveys and a 14-day mobile ecological momentary assessment (mEMA). Simultaneously, participants wore fitness trackers to continuously record heart rate variability (HRV), a non-invasive index of ANS regulation.

Results showed that roughly 21% of participants reported alcohol use, 17% reported marijuana use, and 9% reported nicotine use over the study period. A key finding was the clear association between alcohol consumption and physiological markers: instances of alcohol use were significantly correlated with lower RMSSD (a marker of parasympathetic tone) and a higher LF/HF ratio (a marker of sympathetic-parasympathetic balance). This suggests that alcohol use in this population is tied to measurable ANS dysregulation. Interestingly, while the researchers examined marijuana and nicotine, they did not find significant associations between the use of these substances and the measured HRV indices.

The study highlights that the pandemic environment may have exacerbated substance use, potentially putting women at increased risk for substance use disorders and long-term physiological complications. The researchers argue that HRV, as captured by consumer wearables, shows promise as a clinical biomarker for identifying ANS dysregulation. These findings support the need for universal, routine screening for substance use in pregnant and postpartum care, and suggest that mobile health interventions could provide timely, personalized support to help these women restore autonomic balance and improve health outcomes.