Association of Polymicrobial Growth from Urine Culture with Adverse Pregnancy Outcomes

ABSTRACT

We sought to determine if pyelonephritis and preterm delivery occur more frequently among pregnant women with polymicrobial growth from screening urine culture than among women with negative urine culture. A retrospective cohort study was performed. Three hundred eighty pregnant women with greater than 100,000 colony-forming units per milliliter of polymicrobial growth from urine culture performed at less than 20 weeks of pregnancy were compared with 375 women with negative urine culture. Admissions for pyelonephritis were identified from discharge records. Gestational age at delivery was determined from a research registry. Frequency of pyelonephritis and preterm delivery did not differ between the two groups. Frequencies of pyelonephritis were 0.3% and 0% in women with polymicrobial and negative urine culture, respectively (p = 0.32). Frequencies of preterm delivery were 16.8% and 16% (p = 0.76). Among those with repeat urine cultures, 4.6% in the polymicrobial group and 2.4% of those in the negative initial urine culture group had a positive culture later in the pregnancy (p = 0.21). There is no association between polymicrobial growth from screening urine culture and pyelonephritis or preterm delivery.

KEYWORDS

Asymptomatic bacteriuria - pregnancy - preterm delivery - pyelonephritis

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