Background Maternal undernutrition is one of the most common causes of maternal morbidity and mortality in developing countries. Severe undernutrition among mothers leads to reduced lactation performance which further contributes to an increased risk of infant mortality. However, data regarding nutritional status of lactating mothers at Dessie town and its surrounding areas is lacking. This study assessed dietary diversity, nutritional status and associated factors of lactating mothers visiting health facilities at Dessie town, Amhara region, Ethiopia. Methods Institutional based cross-sectional study was conducted from March to April, 2017 among 408 lactating mothers. Systematic random sampling technique was employed to select the study participants. Data on socio-demographic and economic characteristics, health related characteristics, dietary diversity and food security status of participants were collected using interviewer administered questionnaire. Data were entered into EPI-INFO and analyzed using SPSS Version 22. Bivariate and multivariate analyses were performed to identify factors associated with dietary diversity and nutritional status of lactating mothers. Results More than half (55.6%) of lactating mothers had inadequate dietary diversity (DDS<5.3) and about 21% were undernourished (BMI< 18.5 kg/m(2)). Household monthly income [AOR = 2.0, 95% CI (1.15, 3.65)], type of house [AOR = 1.8, 95% CI (1.15, 2.94)], nutrition information [AOR = 1.6, 95% CI (1.05, 2.61)] and household food insecurity [AOR = 1.8, 95% CI (1.05, 3.06)] were factors associated with dietary diversity of lactating mothers. Being young in age 15-19 years [AOR = 10.3, 95% CI (2.89, 36.39)] & 20-29 years [AOR = 3.4, 95% CI (1.57, 7.36)], being divorced/separated [AOR = 10.1, 95% CI (1.42, 72.06)], inadequate dietary diversity [AOR = 3.8, 95% CI (2.08, 7.03)] and household food insecurity [AOR = 3.1, 95% CI (1.81, 5.32)] were factors associated with maternal undernutrition. Conclusion The dietary diversity of lactating mothers in the study area was sub optimal and the prevalence of undernutrition was relatively high. Public health nutrition interventions such as improving accessibility of affordable and diversified nutrient rich foods are important to improve the nutritional status of mothers and their children in the study area.
