BackgroundThe Lake and Western Zones of Tanzania that encompass eight regions namely; Kagera, Geita, Simiyu, Shinyanga, Mwanza, Mara Tabora and Kigoma have consistently been reported with the poorest Maternal Newborn and Child Health (MNCH) indicators in the country. This study sought to establish the provision of Emergency Obstetric Care (EmOC) signal functions and reasons for the failure to do so among health centers and hospitals in the two zones.MethodsAll the 261 public and private hospitals and health centers providing Obstetric Care services in Lake and Western Zones were surveyed in 2014. Data were collected using questionnaires adapted from the Averting Maternal Deaths and Disabilities (AMDD) tool to assess EmOC indicators. Managers in all facilities were interviewed and services, medicines and equipment were observed. Spatial Mapping was done using a calibrated Global Positioning System (GPS) Essential Software for Android and coordinates represented on digitalized map with Arc Geographical Information System (GIS) software. Population data were according to the 2012 Housing and Population National Census.ResultsIn total 261 health facilities were identified as providers of Obstetric care services, including 69 hospitals and 192 health centres which constitute an overall facility density of 8 per 500,000 population. The three most common EmOC signal functions available in the 3 months preceding the survey were oxytocics (95.7%), injectable antibiotics (88.9%) and basic newborn resuscitation (83.4%). The lowest proportions of facilities performed Cesarean section (25.7%) and blood transfusion (34.6%). Policy restrictions were the most frequent reasons given in relation to nonperformance of blood transfusion and Cesarean section when needed. Lack of training and supplies were the most common reasons for non availability of assisted vaginal delivery and uterine evacuation. Overall the Direct Case fatality Rate for direct obstetric causes was 3%. The referral system highly depended on hired or shared ambulance.ConclusionThe provision of EmOC signal functions in Lake and Western zones of Tanzania is inconsistent, being mainly compromised by policy restrictions, lack of supplies and professional development, and by operating under lowly developed referral services.