Gender Disparities in Reporting

Why Do Women Report More?

The gender gap in VAERS reporting is not unique — it's consistent with broader patterns in healthcare utilization and adverse drug reaction reporting worldwide. Several factors contribute:

• Healthcare engagement: Women are more likely to visit healthcare providers, seek preventive care, and receive vaccines — creating more opportunities for reporting
• Immune response differences: Research suggests women may experience stronger immune responses to vaccines, potentially leading to more noticeable side effects
• Reporting behavior: Studies consistently show women are more likely to report adverse drug reactions across all medication categories, not just vaccines
• Pregnancy-related reporting: Vaccines given during pregnancy generate additional reporting from both the patient and their healthcare provider
• Occupational exposure: Women represent a majority of healthcare workers, who are often required to receive certain vaccines and report adverse events

2026 Update: Gender Trends in Recent Data

The gender gap in VAERS reporting has remained remarkably stable through 2026. Even as COVID-19 booster campaigns wound down and reporting returned closer to pre-pandemic baselines, women continued to file the majority of reports. For the 2025-2026 flu season vaccines, women accounted for approximately 62% of adverse event reports — slightly higher than the overall historical average, consistent with higher flu vaccination rates among women.

The new RSV vaccines authorized in 2023-2024 for older adults and pregnant women added a notable data point: maternal RSV vaccination reports were almost exclusively filed by women, as expected, but the gender split for the 60+ population receiving RSV vaccines was closer to 55/45 — narrower than most other vaccine categories.

Gender and Outcome Severity

While women file more reports overall, the rate of serious outcomes (deaths, hospitalizations) per report tends to be similar across genders. This suggests the gender gap is primarily in reporting behavior, not in the severity of adverse events experienced.

The 172,154 reports with unknown gender (9%) represent a significant data limitation. Many older reports and manufacturer-submitted reports do not include gender information.