Urinary tract infections are common in women, especially pregnant women. It is estimated that each year, Vietnam has about 8.3 million visits for urinary tract infections, and 1 in 5 women who visit the clinic suffer from an infection during pregnancy.

The second cause is due to the growth of the uterus. The uterus grows in size, pressing on the bladder, increasing pressure on the bladder. This makes it difficult to completely empty the bladder during urination, and residual urine is a predisposing factor for infection.