Background Over the last several decades, global efforts to end female genital mutilation/cutting (FGM/C) have intensified through combined efforts of international and non-governmental organizations, governments, and religious and civil society groups. One question asked by donors, program implementers and observers alike is whether there is any evidence that FGM/C is declining. In the last two decades, reliable data have been generated in numerous countries through major household surveys, including repeat cross-sectional surveys. What can we learn from these data? We explore this question by analyzing data on FGM/C obtained from women aged 15–49 in two successive household surveys in Senegal (2005 and 2010–11). The aggregate national-level statistics suggest that there has been no significant change in the prevalence of FGM/C among adult women. These figures are, however, unadjusted for potentially confounding factors, and potentially mask important variation in the practice.This paper aims to provide a deeper understanding of trends in FGM/C across regions, and possibly across generations, providing evidence as to when and where the practice of FGM/C is changing. We aim to answer the following questions: 1. What are the trends in FGM/C among women across Senegal and within regions? 2. Are individual characteristics, such as education, wealth and ethnicity, associated with a likelihood of FGM/C? 3. Are community-level factors, captured by covariate-adjusted geographic estimates, important predictors of a likelihood of FGM/C, as predicted by social convention theory?4. After adjusting for individual- and community-level factors, do we see a decrease in the prevalence of FGM/C across generations of women in Senegal?MethodsParticipants were 14,602 and 14,228 respondents from two consecutive Senegal Demographic and Health Surveys from 2005 to 2010 (FGM/C prevalence 30.1% in 2005 and 28.1% in 2010). A Bayesian geo-additive mixed model based on Markov Chain Monte Carlo techniques was used to map the change in the spatial distribution of FGM/C prevalence at the regional level during the five-year period, while simultaneously examining the effect of individual-level risk factors.ResultsOverall, the prevalence of FGM/C at that national level changed little over the 5-year period, but the fully-adjusted model and map of trends in residual spatial effects at the regional level reveal important spatial patterns. Across both survey periods, several high prevalence regions remained “hot spots,” bearing a consistently high FGM/C prevalence. These include Kolda (along with the newly subdivided region of Sédhiou in 2010), Tambacounda (along with the newly subdivided region of Kédougou in 2010), and Matam. At the same time, risk remained not significant in the high prevalence regions of Saint Louis and Zinguinchor and was attenuated between 2005 and 2010–11 in Kaolack (including the newly subdivided region of Kaffrine in 2010), shifting from not significant risk in 2005 to a very low FGM/C prevalence in 2010–11. In both surveys, unadjusted estimates of the effect of age show no significant difference in risk of FGM across age cohorts. However, non-parametric covariate-adjusted estimates show that in both surveys age is a significant risk factor for FGM/C, although not in the anticipated direction. The effect of age on prevalence of FGM/C is highest in women aged 15–20, and declines with increasing age. Other significant factors are socio-demographic variables, particularly ethnicity.ConclusionsFindings from two consecutive surveys reveal that while no significant changes in FGM/C prevalence are found at the national level, mixed changes are visible at the regional level, as well as at the individual level. The modelled covariate results confirmed that the patterns of FGM/C differ markedly with region of residence and age remaining significant risk factors in both surveys, suggesting that community factors (convention theory), above and beyond individual factors, play a crucial role in the perpetuation, spread or decline of the practice of FGM/C.There is a clear pattern of regions with higher prevalence of FGM/C, mostly the south-eastern region of Tambacounda, Kolda and Matam in 2005, including the eastern region of Kédougou and the southern region of Sédhiou in 2010, which were associated with a higher prevalence of FGM/C, while regions such as Louga, Thiès, Diourbel, Kaolack and Fatick in 2005 and Louga, Thiès, Diourbel, Fatick, Kaolack and Kaffrine in 2010 were associated with a lower prevalence of FGM/C.However, the total spatial residuals in both surveys also indicate that much of the variation in FGM/C likelihood remains to be explained. The spatial effects of the Kaolack region in 2005 was greatly attenuated after multiple adjustments of other risk factors indicating that perhaps the higher number of FGM/C affected women living in the region was inflated by other factors such as ethnicity, socio-economic status and education. Overall, the results indicate that across surveys, certain high prevalence regions remain “hot spots” regarding FGM/C prevalence.These novel findings fit with predictions of theory on social norms and conventions which suggest that the practice is upheld by interdependent expectations regarding the practice, and when such expectations are challenged within a community, the possibility for abandonment is opened.