Background
Ethiopia is one of the countries with the highest maternal mortality ratio 676/100,000 LB and the lowest skilled delivery at birth (10 %) in 2011. Skilled delivery care and provision of emergency obstetric care prevents many of these deaths. Despite implementation of birth preparedness and complication readiness packages to antenatal care users since 2007 in the study area, yet an overwhelming proportion of births take place at home. The effect of birth preparedness and complication readiness on place of delivery is not well known and studied in this context.

Methods
A community based case control study preceded by initial census was conducted on a total of 358 sampled respondents (119 cases and 239 controls) who were selected using stratified two stage sampling technique. A pre-tested and standardized questionnaire with a face-to-face interview was used to collect the data, and then data was cleaned, coded and entered in to SPSS version-21 for analysis. Binary logistic regression models were run to identify predictors of place of delivery and Odds ratio with 95 % CI was used to assess presence of associations at a 0.05 level of significance.

Results
The mean (± Standard Deviation) age of respondents was; 27.41(±5.8) and 28.84(±5.7) years for the cases and the controls respectively. Two third (67.1 %) of the childbirths took place in the respondents house while only (32.9 %) gave birth in health facilities. Great proportion (79.7 %) of the cases and two third (34.0 %) of the controls were well-prepared for birth and complication. Maternal education, religion, distance from health facility, knowledge of availability of ambulance transport and history of obstetric complication were significantly associated with place of delivery (P-value <0.01). Birth preparedness and complication readiness practice had an independent effect on place of delivery (AOR =2.55, 95 % CI: 1.12, 5.84).

Conclusion
The study identified better institutional delivery service utilization by mothers who were well-prepared for birth and complication. Strategies that increase the preparedness of mothers for birth and complication ahead of childbirth are recommended to improve institutional delivery service utilization.