It is estimated that several hundred million women suffer from urinary tract infection annually, with costs to health care providers amounting to over $6 billion annually worldwide, a figure that may even be an underestimate [1].

It is estimated that 2 to 10% of pregnant woman suffer from any form of urinary tract infections [2]. These infections complicate up to 20% of pregnancies and are responsible for the majority of ante-partum admissions to the maternal–fetal medicine units [3].

Urinary tract infection (UTI) occurs frequently in pregnancy with a large number of infections being asymptomatic. The frequency of asymptomatic bacteriuria (ASB) in pregnancy accounts for the rationale of urinalysis throughout pregnancy period [4].

It can be associated with varieties of adverse obstetric outcome and medical conditions such as the development of acute and chronic pyelonephritis, preterm labour, low birth weight, pre eclampsia, chronic renal disease, and prenatal mortality [5]. Undiagnosed and untreated bacteriuria in pregnancy represents a considerable risk factor for acute pyelonephritis in approximately 5% of pregnant women with increased risk of low birth weight and prenatal fatal death [6].

Detection and treatment of bacteriuria has been reported to prevent up to 80% cases of pyelonephritis [7]. Bacteriuria in pregnancy usually reflects prior colonization e.g. at the time of onset of sexual activity rather than acquisition during pregnancy itself [8]. Furthermore, there is obviously a substantial risk that the infecting pathogens are becoming resistant to empirically prescribed antimicrobial agents normally used in the community.

Study design: It was a Cross sectional study

Study place: The study was conducted in the department of Microbiology, Peoples College of Medical Sciences & Research Center, Bhopal (M.P).

Study duration: July 2015 to March 2016.

Sample size: A total number of 210 pregnant women attended antenatal clinic and had asymptomatic bacteriuria during the period of July

Positive control: Staphylococcus aureus ATCC 25923.

Negative control: Escherichia coli ATCC 25922.

Biochemical reactions: Following biochemical test were put up to identify bacteria to species level such as catalase, coagulase for gram positive and oxidase, indole, citrate, urea, triple sugar iron, lysine decarboxylase, arginine and ornithine and motility testfor Gram negative bacteria following standard procedure.

Out of 210 urine samples of ANC Women examined for asymptomatic bacteriuria, 17 were having significant bacteriuria (10⁵cfu/ml) giving frequency rate of 8.09%.

The frequency of asymptomatic bacteriuria according to age distribution showed that majority of the subjects screened were in the age group of 21-30 years, Women in age group 21-30 years showed the highest incidence of asymptomatic bacteriuria (70.58%) is shown in Table 1.

Table No.-1: Frequency of ASB in relation to age distribution of pregnant women

In the present study, the frequency of asymptomatic bacteriuria was 8.09% (17 cases) among the sampled population of 210 pregnant women attending ante-natal clinic. Similar observations were found by other authors [15] although R Sujata et al found it to be 3% which is less than our study [16]. This variation may be explained by the differences in the environment, social habits ofthe community, the standard of personal hygiene and education. In the present study, the subjects in the age groups of 21-30 years showed the highest frequency of infection (70.58%). Study conducted by Lavanya et al [17] reported higher frequency in subjects belong to the age group of 25-30 years, although R Sujata et al [16] found that the age group of 21-30 yrs had higher frequency of infection (72.72%). In other study conducted by Kasinathan A et al [18] subjects belong to the age group of 26-30 years had maximum frequency of infection (59.1%) which is lower than the present study.

Among positive cultures which were obtained 17.64% belonged to primigravidae and 29.41% belonged to multigravidae in contrast to study by R. Sujata et al. which showed 48.9%in primigravidae and 51.1% belonging to multigravidae [16]. There was no difference in frequency of urinary tract infection in pregnant women with previous history of urinary tract infection and those without.

In the present study, it was observed that the women in their second and third trimester had higher frequency of asymptomatic bacteriuria (52.94%), and this could be attributed to the anatomical and physiological changes experienced by pregnant women during these stage of pregnancy, for instance the uterus expands and also there are increased hormonal effects which together offset normal homeostatic balance making conditions favorable for microbial invasion.

Though frequency of UTI in the first trimester was low it could only be that it served as incubation period for most of the microbes, only for microbial invasion to be manifest in the second and third trimester [19].

In the present study it was observed that Escherichia coli was the most common isolated organism in 9 (52.94%) subjects followed by Staphylococcus aureus 4 (23.52%), Klebsiella pneumonia 2(11.76%) among the isolates.