Objective To explore the relationship between macro-economic indicators and incidences of adverse events linked to intrauterine devices (IUDs). Methods Data on IUD-associated adverse events were collected from a cohort study conducted between September 2005 and December 2006. Regional economic data were from the 2006 National Economic and Social Development Statistical Bulletins and Statistical Yearbooks of various regions. A total of 20,220 IUD users in 236 towns in Jiangsu, Shanghai, Guangdong, Anhui, Sichuan, and Chongqing provinces in China were included in this study. Linear correlation and regression analyses were used to analyze the relationships between regional income and total incidences of adverse events, incidences of mild adverse events, and incidences of severe adverse events. Results Incidences of total adverse events and mild adverse events were positively correlated with regional economic level (rs=0.336, Plt;0.05; rs=0.272, Plt;0.05), while incidences of severe adverse events were not correlated with regional economic level. Conclusions The positive relationship between regional economic level and reported IUD-associated mild adverse events likely reflects income-related disparities in women seeking care and receiving treatment for mild adverse events. This points to a need to improve both public health education and the quality of health services, particularly in poorer areas.