In general, urinary tract infections are mostly associated with poor hygiene, with about 50% of women having at least one urinary tract infection and 20% having multiple infections – many women have 1-2 a year, which is quite common. Usually these bacteria are harmless when they are in the vagina, and the problem begins when they enter the urethra. Those women who develop urinary tract infections urinary tract infections mostly refer to pyelonephritis, cystitis and urethritis. Due to the special physiological environment during pregnancy, they are prone to urinary tract infections for the following reasons: 1. The kidneys filter more nutrients such as glucose, amino acids and water-soluble vitamins during pregnancy, so the content of these substances in the urine increases, providing material conditions for bacterial growth. 2.The ureter thickens, lengthens and flexes during pregnancy, peristalsis decreases, and some urine remains in the ureter after urination, making conditions for bacteria to multiply. When urinating, the bladder contraction increases the pressure in the bladder, which can cause some urine to flow backwards into the ureter, and it is not easy to drain back to the bladder, leading to upstream infection. 4, at the time of delivery, due to the fetal head squeeze, so that the bottom of the bladder is congested, edema, easily lead to local injury and infection. 5, pregnant women do not pay attention to the hygiene of “intercourse”, increased secretions, do not pay attention to cleaning the labia and vaginal vestibule, it is easy to contaminate the urethral opening. Possible symptoms 1, abnormal urination: urinary tract infection common abnormal urination is urinary frequency, urinary urgency, painful urination, can also see urinary incontinence and urinary retention. Polyuria may be seen in the early stages of chronic renal failure caused by chronic pyelonephritis, and oliguria or anuria may occur in the later stages. 2, abnormal urine: Urinary tract infection can cause abnormal changes in urine, commonly bacterial urine, pus urine, hematuria and gas urine. 3.Lower back pain: lower back pain is a common clinical symptom, and kidney and perirenal diseases are one of the common causes of lower back pain. When the kidney envelope, renal pelvis and ureter are stimulated or tension is increased, they can cause painful sensation in the lumbar region, and lower urinary tract infections usually do not cause lumbar pain. Inflammation of the kidney and perinephric area, such as renal abscess, perinephritis, perinephric abscess, and acute pyelonephritis, often cause persistent and severe swelling and pain in the lower back, and back pain caused by chronic pyelonephritis is often sore. In acute infections, bed rest should be taken, more water should be drunk, and urination should be diligently performed to reduce the retention of bacteria in the bladder, which is conducive to infection control. Women should pay attention to the cleanliness of the vulva, and washing or wiping of the vulva should be done in the direction of the anus from the front to reduce the chance of bacterial contamination. The clinical use of broad-spectrum, low-toxicity, potent, and not easy to produce drug resistance drugs. Commonly used are cotrimoxazole, furotanidine, flufenamic acid, hydroxybenzyl penicillin, cephalosporin antibiotics and so on. The use of drug treatment is best carried out under the guidance of a doctor. The recurrence of urinary tract infection must find the regular hospital examination and treatment.