Background and aim: Urinary tract infection (UTI) is the most common bacterial infection in pregnancy and is associated with premature delivery and low birth-weight infants. We aimed to determine the virulence factors of uropathogenic Escherichia coli (UPEC) strains isolated from pregnant women with or without clinical signs and symptoms of UTI and their association with antimicrobial resistance pattern.  Methods: Isolation and detection of UPEC isolates, antimicrobial susceptibility followed by phenotypic detection of ESBL and biofilm production. Virulence and resistant genes were amplified by PCR. Results: Urine samples collected from 432 pregnant women of which significant bacteriuria represented 155/432 (35.9%). Patients were divided into 4 groups: cystitis, pyelonephritis, asymptomatic bacteriuria (ASB) and insignificant bacteriuria. UPEC was the most frequent organism 58/155 (37.4 %). The highest resistance rates were against ceftazidime and lowest resistance was to fosfomycin. ESBL producing UPEC represented 24/58 (41.4%) of samples while biofilm formation was 32/58 (55.2%). Moreover, 54/58 (93.1%) of UPEC isolates were found to be MDR. However, 53.1% of positive biofilm isolates were ESBL positive, all biofilm-producing isolates were MDR. Generally, fimH, fyuA and iutA genes were the most frequently detected virulence genes. Pap G and afa genes were significantly higher among patients with pyelonephritis. Pap G, and IutA genes were more frequent in positive biofilm group. Conclusion: Most of the isolates were MDR. Fosfomycin can be used precautionary in resistant cases. Biofilm producing isolates were more resistant to antibiotics and higher virulent than non-biofilm producers.