Background
Optimal breastfeeding is inextricably linked to the achievement of Millennium Development Goals (MDGs) of eradicating extreme poverty and hunger, reducing child mortality and improving maternal health. Breastfeeding is safe, promotes sensory and cognitive development and contains antibodies that protect infants from common childhood illnesses. The objective of this study was to assess suboptimal breastfeeding and its determinants factors among mothers who have children below 23 months old in Debre Berhan, Ethiopia.

Methods
A community based cross sectional study was conducted from 1 March 2015 until 30 March 2015. Five hundred forty eight mothers were included in the study using a two stage sampling technique. The data was collected by trained data collectors through pretested semi structured questionnaire. The collected data were cleaned, coded, entered and then analyzed using SPSS version 20 windows program. Descriptive statistics, binary and multivariable regression analysis with 95 % confidence interval was carried out and p value less than 0.05 used to determine the significant association. Late initiation of breastfeeding was defined as initiation of breastfeeding after one hour of delivery while early cessation of breastfeeding was to stop breastfeeding before 24 months of age. According to World Health Organization exclusive breastfeeding was defined as the practice of feeding breast milk only, including expressed breast milk, to infants and excluding water, other liquids, breast milk substitutes, and solid foods. Vitamin drops, minerals, oral rehydrating solution (ORS) and medicines may be given.

Results
The prevalence of late initiation of breastfeeding, not exclusively breastfeeding and early cessation of breastfeeding were 17.5 % (95 % Confidence Interval [CI] 15.2 %, 19.4), 49.8 % (95 % CI 46.3, 50.5) and 12.8 % (95 % CI 11.7, 14.1) respectively. Birth at home was significantly associated with late initiation of breastfeeding (Adjusted Odds Ratio [AOR] 3.0; 95 % CI 1.5, 6.0). No advice during antenatal care was a predictor of not exclusively breastfeeding (AOR1.7; 95 % CI 1.2, 2.5). Being illiterate (AOR 3.2; 95 % CI 1.2, 8.3) and no advice during antenatal care about breastfeeding (AOR 1.9; 95 % CI 1.0. 3.4) were significantly associated with early cessation of breastfeeding.

Conclusion
Educational status, age, antenatal and postnatal follow up, resident and place of delivery were predictors of suboptimal breastfeeding. Integrated and targeted interventions were recommended to achieve a better outcome in minimizing the late initiation, non-exclusive and early cessation of breastfeeding.