BACKGROUND: There is growing evidence that climate-related disasters increase rates of intimate partner violence (IPV) against women. However, there are only limited understandings of the size and nature of such associations needed to inform appropriate programming. Gaps in evidence are particularly pronounced in the Pacific-one of the regions most at risk of increased disasters from climate change. METHODS: We analysed data from 450 men and 707 women collected as part of cross-sectional study of IPV experience, risk and protective factors in rural Samoan villages. Data were analysed using multivariable logistic regression models to assess associations between (1) men's and women's exposure to climate-related disasters and their mental health and (2) women's exposure to climate-related disasters and their risk of IPV in the previous 12 months. FINDINGS: Reported symptoms of depression and anxiety were associated with having experienced a disaster. Those who reported experiencing a disaster 2-3 times had 61% greater odds of reporting depression (OR 1.61
95% CI 1.00 to 2.58) and 88% greater odds of reporting anxiety (OR 1.88
95% CI 1.01 to 3.49), in comparison to those who reported never experiencing a disaster. Women who reported experiencing 2-3 disasters had more than twice the odds of experiencing recent IPV (adjusted OR, aOR 2.37, 95% CI 1.77 to 3.19), while those who reported experiencing 4+ disasters had over 8 times the odds (aOR 8.12
95% CI 2.02 to 32.61). INTERPRETATION: This is one of the first studies in the Pacific region to provide quantitative evidence of associations between exposure to climate-related events and women's experiences of IPV. We identify a clear dose-response relationship between higher exposure to climate-related events and an increased risk of IPV for women. This points to the role of cumulative stress from experiencing repeat disasters in driving higher rates of IPV in climate-affected regions.