The methods were previously described in our study on “Urinary Bacterial Profile and Antibiotic Susceptibility Pattern of UTI among Pregnant Women in North West Ethiopia” except few differences .
Study site, study population, duration of study and data collection
A hospital based cross sectional study was conducted at Felege Hiwot Referral Hospital (FHRH) from January 2011 to April 2011 to determine associated risk factors of urinary tract infection (UTI) among pregnant women.
A pre-designed and structured questionnaire was used for the collection of data on associated risk factors. Collection of information on sign and symptoms of UTI and physical examination of pregnant women were done by Gynecologists and senior nurse.
Pregnant women who were taken antibiotics within seven days at the time of recruitment and who were not willing to participate were excluded from this study.
Specimen collection and processing
Clean catch mid-stream urine samples were collected using sterile, wide mouthed glass bottles with screw cap tops. The pregnant women were also informed to clean their hands with water and then cleanse their periurethral area with sterile cotton swab soaked in normal saline to reduce the risk of contamination. Urine specimens were processed in the laboratory within 2 hours of collection and specimens that were not processed within 2 hours were kept refrigerated at 4°C until it was processed.
A calibrated sterile platinum wire loop was used for inoculation of specimens in to the culture media. It has a 4.0 mm diameter designed to deliver 0.01 ml. A loopful of well mixed urine sample was inoculated MacConkey, Manitol Salt Agar and Blood Agar (Oxoid, Ltd, England).
All plates were then incubated at 37°C aerobically for 24 hrs. The plates were then examined macroscopically for bacterial growth. The bacterial colonies were counted and multiplied by 100 to give an estimate of the number of bacteria present per milliliter of urine. A significant bacterial count was taken as any count equal to or in excess of 10,000 CFU/ml [3, 7, 8].
Mid-stream urine specimen: - a specimen obtained from the middle part of urine flow: Clean catch urine specimen.
Symptomatic UTI refers to patients whose urine is yielding positive cultures (≥ 105CFU/ml) and who have symptoms referable to the urinary tract.
Asymptomatic bacteriuria (ASB) refers to the presence of two consecutive clear-voided urine specimens both yielding positive cultures (≥ 105CFU/ml) of the same uropathogen, in a patient without urinary symptoms.
Maternal Anaemia is defined as haemoglobin concentration less than 11 g/dl.
Parity is the number of pregnancy reaching viability or beyond stage of abortion (before 20 weeks/less than 500 g BW).
Gestational Age is the age of the fetus estimated by computing from the first day of the last menstrual period (time that precedes conception) until the day of consultation.
History of UTI is any history of infection pertaining to the urinary tract diagnosed by a physician.
Pregnant women were informed to clean their hands with water and their genital area with swab soaked in normal saline before collection of the clean catch midstream urine samples. All specimens were transported from the hospital to regional laboratory within cold box and those specimens which were not processed with in 2hrs were kept in refrigerator and processed no longer than 18 hours after collection.
Only specimens which produced ≥ 105CFU/ml of urine were considered significant but specimen who produced < 105 colonies/ml of urine considered insignificant or due to contamination. Culture media were sterilized based on the manufactures instruction. Then the sterility of culture media were checked by incubating 3–5% of the batch at 35 – 37°C overnight and observed for bacterial growth. Those media which showed growth were discarded. The standard reference strains; Staphylococcus aureus (ATCC25923), Escherichia coli (ATCC25922) and P. aeruginosa (ATCC 27853) were used for testing quality of culture media.
The study was conducted after getting a full approval by the health research unit of Jimma University, Amhara national regional state health bureau and FHRH. In addition written informed consent for the study was obtained from the study participants and confidentiality of results was kept. The results of urine tests were sent to the responsible person as soon as possible so that the pregnant women could be benefited from the study.