Dissertation (MSc Midwifery)Background: Modes of delivery (birth of a baby) are spontaneous vaginal delivery and caesarean section. Throughout the modern obstetric and midwifery practice understanding, vaginal birth is and has been considered to be the preferred mode of delivery while caesarean birth is reserved only when it’s obstetrically indicated to save the life of the mother and/or the unborn baby and therefore, improve obstetric outcomes. The effect of mode of delivery on other outcomes, such as maternal and newborn outcomes, and psychological or social well-being are still unclear. Hence there is need to understand mode of delivery and obstetrics outcomes among primigravida. Objective: The aim of this study was to explore at the mode of delivery, rationale for Caesarean section, an association between mode of delivery and obstetric outcome. Methods: This was an analytical cross sectional study involving 356 primigravida obtained through purposive sampling from Iringa municipality. Questionnaire and check list were used to collect information, and the data collected were analysed using SPSS 20 version. Both descriptive and inferential statistics were used in the data analysis and presentation. Results: During the study period, a total of 1314 deliveries took place in the studied facilities out of which, 356 (27%) involved primigravida. Among them, 209 (58.7%) delivered by spontaneous vaginal delivery and 147 (41.3%) delivered by caesarean section. More than a half (73%) of 356 primigravida was in age group 20-35 years. Likewise a new born delivered by caesarean section are more likely to have birth asphyxia compared with those newborns delivered by spontaneous vaginal delivery (AOR 3.303,P< 0.001). Conclusion: Mode of delivery among the primigravida appears to predict the outcome and has an influence on mode of delivery in subsequent pregnancies. Our study revealed that Caesarean Section rate was 41.3% which was higher compared to WHO recommendation, and therefore there is need to address the rationale for indications for Caesarean section and contributing factors for non rational Caesarean section.