For decades, Africa has been plagued by political and ethnic conflict, the health ramifications of which are often not investigated. A crisis occurred recently in Kenya following the 2007 presidential election. Ethnic violence ensued, targeting the incumbent President Kibaki's Kikuyu people. The violence occurred primarily in Nairobi and the Rift Valley of Kenya. We sought to examine the association between exposure to the 2007/2008 Kenyan Crisis and birthweight. Using the 2008/2009 Kenyan Demographic and Health Survey (KDHS), we compared birthweights of infants in utero or not yet conceived during the 15 months after the political turmoil following the 2007 presidential election (exposed) to those who were born before the crisis (unexposed). There were 663 "exposed" and 687 "unexposed" infants. Multivariate regression was used. We examined the possibility of two-way and three-way interactions between exposure status, ethnicity (Kikuyu versus non-Kikuyu), and region (violent region versus not). Overall, exposure to the Kenyan Crisis was associated with lower birthweight. Kikuyu women living in a violent region who were exposed during their 2nd trimester had the greatest difference in birthweight in comparison to all unexposed infants: 564.4g lower (95% CI 285.1, 843.6). Infants of Kikuyu exposed during the 2nd trimester and living in a violent region weighed 603.6g less (95% CI 333.6, 873.6) than Kikuyu infants born during the unexposed period. Political unrest may have implications for the birthweight of infants, particularly among targeted populations. Given the adverse sequelae associated with lowered birthweight, these results suggest that particular attention should be paid to pregnant women and targeted ethnic groups following such events.