Japanese Cohort Study Links Frequent Antibiotic Use to Increased Risk of Severe Maternal Psychological Distress

Study of 94,000 women finds antibiotic use before and during pregnancy increases psychological distress. Learn how gut health impacts maternal wellness.

By: AXL Media

Published: Apr 1, 2026, 11:38 AM EDT

Source: Information for this report was sourced from University of Toyama

New Research Links Antibiotic Exposure to Perinatal Mental Health

A sweeping study involving over 94,000 participants has identified a significant correlation between the use of antibiotics and the onset of psychological distress during early to mid pregnancy. The research, spearheaded by Professor Kenta Matsumura and published in the journal BMC Public Health, suggests that the timing and frequency of antibiotic consumption are critical factors in maternal mental well-being. By examining a vast dataset from the Japan Environment and Children’s Study, investigators have highlighted a potential new environmental risk factor for perinatal depression, a condition that threatens both maternal health and long term fetal development.

Establishing the Scope of Maternal Distress and Antibiotic Trends

The investigation utilized data from women primarily at the 12 week mark of gestation, following their progress through the 15 week interval to capture a snapshot of early pregnancy mental health. Researchers categorized the subjects based on their antibiotic history, distinguishing between those who avoided the medication, those who used it in a single period either before or after conception, and those who utilized it across both timeframes. This structured approach allowed the team to move beyond simple correlation and look for patterns in how cumulative exposure might exacerbate mental health challenges during a vulnerable biological window.

The Correlation Between Treatment Frequency and Psychological Strain The statistical analysis revealed a clear, stepwise escalation in the likelihood of mental health struggles as antibiotic exposure increased. According to Professor Kenta Matsumura, the adjusted odds ratios for severe psychological distress reached 1.50 for women who reported using antibiotics both before and during early pregnancy. These findings indicate that while occasional use carries a marginal risk, repeated courses of antibiotics are associated with a much higher probability of reaching clinical thresholds for severe distress, even after accounting for variables such as income, education, and previous psychiatric history.

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