Dissertation (MMED Microbiology And Immunology)Introduction Significant bacteriuria during pregnancy can lead to serious obstetric complications, poor maternal and perinatal outcomes. The purpose of this study was to determine the prevalence and antibiotic susceptibility pattern of significant bacteriuria among pregnant women at Makole health centre Dodoma city, Tanzania. Methodology This was a cross sectional study conducted from February 2020 to April 2020. During this period two hundred consenting pregnant women, aged 18 years and above, at any gestation age were enrolled at Makole Health Centre. Mid-stream clean catch urine samples were collected and transported to Dodoma regional referral hospital laboratory in cool boxes packed with ice parks for microbiologic examination. Urine culture, identification tests and bacterial susceptibility pattern were done as per standard operating procedures and the clinical and laboratory standards institute (CLSI) standard guidelines. Chi squared tests and logistic regression were done to identify factors associated with asymptomatic bacteriuria. A p value < 0.05 was considered statistically significant. Results Out of 200 pregnant women studied, 24 (12%) had significant bacteriuria (mid-stream urine culture of at least 105 CFU/mL) in which Escherichia coli was the most prevalent isolated bacterium with 8 isolates (33.3%). Other isolated bacteria were Klebsiella species 1(4.1 %), Enterobacter species 1(4.1%), Pseudomonas aureginosa 1(4.1%), Streptococcus Species 1(4.1%), Coagulase negative Staphylococcus 6 (25%), and Staphylococcus aureus 6 (25%). Antimicrobial sensitivity test results showed that all 8 E. coli isolates were 100% sensitive to nitrofurantoin but they were 75% resistant to ceftriaxone. The 6 Staphylococci aureus isolates showed (100%), 83.3%, 66.7%, 66.7% and 50% resistance to penicillin, erythromycin, amoxicillin, cephalexin and Amoxicillin & clavulanic acid respectively. The 6 Coagulase negative Staphylococcus isolates were 100% resistant to amoxicillin and penicillin. Gestation age and previous history of UTI had statistically significant association for the development of bacteriuria among the study participants with p =value of 0.0472 and 0.0471 respectively. Conclusion The prevalence of significant bacteriuria among the study participants was high. Variable pattern of antibiotic resistance pattern was observed among bacterial urinary isolates with alarming levels to one of the first line recommended antibiotics in pregnancy, amoxicillin and clavulanic acid.These findings suggest for improved screening and treatment of pregnant women for significant bacteriuria to avert associated complications.