Mental illness affects more women than men in the United States. Poor mental health in reproductive-age women has negative implications on population health. The purpose of this quantitative, correlational study was to examine the relationship between household structure and frequency of mental distress, with consideration of the mediation social-emotional support provides for reproductive-age women. The social ecological model was the theoretical framework for this research, in which frequency of mental distress related to the individual-level of the human-environment interaction construct. Household structure and social-emotional support were examined at the relationship-level. Pearson's correlation coefficient and linear regression were used to conduct a cross-sectional analysis of the 2010 Behavioral Risk Factor Surveillance System data set with a total sample size of 65,269 women, 18-44 years old. The confounding variables, health care access, race, income, marital status, number of children in the household, and pregnancy status, were included in the analysis. Although social-emotional support significantly influenced both household structure and frequency of mental distress, significance was not found between household structure and frequency of mental distress indicating that mediation does not exist. This study provides researchers and practitioners information about household structure that should be considered when designing innovative, nonprofessional support programs at the community-level. Positive social change implications include an understanding of the relationship between complex variables associated with social-emotional support, which could improve community support programs focused on mental health wellness of reproductive-age women.