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Bacteria in urine in pregnancy
Last reviewed: 05.07.2025

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Bacteria in urine during pregnancy is a signal from the body about pathological processes that require treatment and medical attention. Let's consider the main causes of bacteria in urine, diagnostic methods, symptoms and treatment methods.
During pregnancy, a woman has to take many tests that allow monitoring the health of the expectant mother and her child. Urine analysis is considered one of the most important. Bacteria in urine occur very often, but there is no clear explanation for this phenomenon. Therefore, there is such a thing as bacteriuria of pregnant women.
The presence of bacteria may indicate inflammation in the kidneys. This may be cystitis, pyelonephritis and other diseases, the risk of which increases during pregnancy. However, such a condition does not bring any benefit to either the expectant mother or her future child. And in some cases, it can lead to pathological consequences. Particular danger arises with asymptomatic bacteriuria, in which case the disease proceeds without any manifestations.
Many doctors claim that bacteria in urine detected during pregnancy indicate a high risk of premature birth. Very often, the following bacteria are found in urine: E. coli in 80% of cases, Klebsiella, Proteus, Streptococcus, Enterobacter, Enterococcus faecalis, Staphylococcus and others. Each of these cases requires treatment and medical care.
Causes of Bacteria in Urine During Pregnancy
The causes of bacteria in the urine during pregnancy are very diverse. The constantly growing uterus puts pressure on the kidneys, disrupts their normal functioning, and leads to the appearance of harmful microorganisms. Bacteria can appear due to hormonal changes in the woman's body and physiological features: a short urethra, the ureter is located close to the rectum.
Bacteria appear in women who have sex with many partners and do not maintain personal hygiene at the proper level. In some cases, bacteriuria appears with STIs, diabetes, chronic body lesions and pathologies of the urinary system. Sometimes a weakened immune system and caries lead to the appearance of bacteria in the urine.
There are two types of bacteria in urine: true bacteriuria occurs when bacteria reproduce independently and live in urine. In false bacteriuria, bacteria enter the urine from distant foci of infection through the blood. Increased levels of harmful microorganisms are accompanied by clinical manifestations, but in some cases they do not cause side symptoms.
Bacteria occur in chronic diseases that recur and worsen during pregnancy, let's look at some of them:
Inflammation of the bladder walls is the most common urological lesion of both infectious and non-infectious nature. Infectious cystitis occurs due to opportunistic microflora. Non-infectious cystitis occurs with weakened immunity, hypothermia, intestinal dysbacteriosis, and fatigue. In some cases, vaginal dysbiosis and irritation of the bladder with chemicals lead to the appearance of bacteria in the urine.
If a woman had symptoms of cystitis before pregnancy, then bacteria found in the urine indicate its recurrence. The symptoms of the disease are manifested as frequent urges to urinate, which is very painful. The woman experiences nagging pain in the lower abdomen, blood in the urine and elevated body temperature. With such symptoms, it is necessary to seek medical help.
Inflammatory process in the renal pelvis. Escherichia coli, Staphylococcus aureus, Streptococcus, Candida fungi, Pseudomonas aeruginosa are the causes of the disease. The infectious focus is any inflammatory-purulent process. Pyelonephritis can be primary - occurs at the first signs of pregnancy and secondary - manifests itself even before pregnancy and worsens against the background of hormonal changes.
Bacteria in the urine caused by kidney inflammation appear due to the growth of the uterus, which displaces neighboring internal organs. When the disease worsens, a woman experiences acute pain in the lumbar region, chills, burning during urination, signs of intoxication. Pyelonephritis requires mandatory treatment, since the disease is dangerous for the expectant mother and her child.
In addition to the above reasons, there are also risk groups. Thus, dental problems can lead to bacteria in the urine, irregular hygiene, diabetes, chronic diseases of the genitourinary system, pathologies of the urinary system and sexually transmitted diseases are the main risk factors and causes of bacteriuria.
- Urethritis
A bacterial inflammatory disease that affects the walls of the urethra. The disease is very common and most often affects pregnant women, causing bacteria in the urine. Bacterial urethritis occurs due to the entry of harmful microorganisms into the urethra (E. coli, enterococci, staphylococci and streptococci). If a pregnant woman has chlamydia, this is another cause of urethritis, which can lead to damage to the amniotic fluid and the embryo.
The peculiarity of urethritis is that the pathogens are constantly present on the mucous membranes of the urinary tract. Therefore, the task of the expectant mother and her doctor is to identify the predisposing factors and eliminate them. The disease and bacteria in the urine against its background can appear with injuries and narrowing of the urethra, catheterization of the bladder and during cystoscopy. The bacterial form of the disease can be caused by specific pathogenic microorganisms that destroy the local defense of the woman's body.
Symptoms of bacteria in urine during pregnancy
Symptoms of bacteria in the urine during pregnancy depend on the cause of the disease. Bacteriuria occurs in 10% of pregnant women, the danger is that it can be asymptomatic. Against the background of bacteria in the urine, a woman develops nephrolithiasis and ureter dilation. Very often, these symptoms occur in the third trimester of pregnancy. Bacteria can cause the birth of a child with low birth weight, miscarriage and premature birth.
Various harmful microflora are found with bacteria: intestinal and pseudomonas aeruginosa, proteus, streptococci, staphylococci and other microorganisms. Very often bacteria appear with inflammatory diseases of the kidneys and urinary system, infectious lesions of the body. Harmful microorganisms can get into the urinary tract and kidneys by hematogenous route.
Symptoms of bacteria in urine during pregnancy are similar to those of cystitis and pyelonephritis. The woman's temperature rises, there are frequent and painful urges to urinate, urine with sediment and is cloudy. If such symptoms appear, it is necessary to seek medical help, determine the cause of discomfort and eliminate it.
If bacteria in the urine are caused by urethritis, the woman will experience purulent and mucopurulent discharge from the urethra, pain and discomfort when urinating. With acute inflammation of the urethra, bacteria in the urine become chronic. Bacteria can hide in the Bartholin glands, which are located in the vestibule of the vagina. When the protective properties of the immune system are reduced, bacteria become active and cause painful symptoms and can be detected in a urine test.
Diagnosis of bacteria in urine during pregnancy
Diagnostics of bacteria in urine during pregnancy is carried out every month, as the expectant mother regularly takes tests. This allows maintaining the health of the woman and her future baby. For diagnostics, the reduction glucose test, the Griss nitrite test and other methods are used.
Since diagnostics are performed in a polyclinic setting, doctors perform chemical tests that provide quick results. Bacteriological methods determine the number of microbial colonies and the degree of bacteriuria. If bacteriuria occurs against the background of colonization of the periurethral region that appeared before pregnancy, the disease is considered a risk factor for acute pyelonephritis.
Let's look at the main stages of diagnosing bacteria in urine during pregnancy:
- Instrumental and laboratory studies – ultrasound examination of the kidneys, blood and urine tests, excretory and survey urography, Doppler ultrasound of the renal vessels, screening tests.
- Differential diagnostics – doctors conduct a complete diagnosis of the pregnant woman’s body in order to determine the diseases that caused bacteria in the urine and to identify asymptomatic bacteriuria.
In addition to diagnostic methods, a woman should consult a nephrologist, therapist, urologist and gynecologist. This will provide a complete picture of the causes of the disease and allow an effective treatment plan to be drawn up.
Treatment of bacteria in urine during pregnancy
Treatment of bacteria in urine during pregnancy depends on the results of diagnostics. But every expectant mother should undergo treatment. There are several methods of treatment, let's consider the main ones:
- Non-drug treatment
Pregnant women are recommended to eat foods and drinks that reduce urine pH. It is also recommended to increase urine output.
- Drug treatment
This type of treatment is carried out both for obvious and asymptomatic bacteriuria. The woman is prescribed a 1-3 week course of treatment with cephalosporins, antimicrobial agents and ampicillin. This course of treatment is explained by the fact that a single dose of drugs is not enough during pregnancy. All medications are selected empirically. Antibacterial therapy with subsequent monthly bacteriological urine tests is mandatory. The woman may be prescribed maintenance therapy until the end of pregnancy and for 14 days after delivery. This will help prevent relapses of bacteriuria.
The specifics of treatment also depend on the complications during pregnancy. Let's consider the complications of gestation by trimester:
- Bacteria in urine detected in the first trimester can cause termination of pregnancy. Standard therapy is used for treatment purposes.
- In case of bacteriuria in the second and third trimesters, the woman undergoes oncoosmotherapy to maintain the pregnancy. If bacteria become a threat to premature birth, the pregnant woman undergoes tocolytic therapy.
If bacteria in the urine appeared due to urethritis, then the woman undergoes antibacterial therapy and uroantiseptics. The drug Monural is highly effective, which can be taken only if the therapeutic benefit for the mother is more important than the possible risk to the fetus. Urethritis and bacteria in the urine are treated with Azithromycin, Doxycycline, Phytolysin or Canephron. The drug is selected by the attending physician and its intake is strictly controlled.
In many cases, bacteria in the urine are detected even before pregnancy. The frequency of occurrence of this disease is affected by the condition of the urinary tract and the sphincter mechanism of the bladder. When treating bacteriuria in the early stages of pregnancy, in 80% of cases it is possible to cure the disease without consequences for the body of the mother and child, in 5-7% of cases bacteria lead to miscarriages and prematurity.
Prevention of bacteria in urine during pregnancy
Prevention of bacteria in urine during pregnancy are methods that allow you to prevent the development of the disease and protect the body of the expectant mother. Taking care of your health and the health of the future child is the primary task of every woman. To prevent bacteriuria, the expectant mother needs to:
- Regularly submit urine for analysis, for reliable results it is necessary to use only sterile containers. Before submitting tests it is forbidden to consume alcohol, spicy and salty foods. Urine should be collected after washing, in the morning. Please note that no more than 2 hours should pass from the moment of urine collection to the laboratory test, as the composition of urine changes.
- A pregnant woman should maintain genital hygiene and avoid wearing synthetic underwear. Synthetic underwear provokes the growth of pathogenic microorganisms, promotes the development of candidiasis and the appearance of bacteria in the urine in an ascending manner.
- Following your doctor’s recommendations, regular check-ups and taking prescribed medications will help protect you from pathological changes during pregnancy.
- Prevention of urethritis caused by bacteria in the urine should begin with observing the rules of hygiene and a healthy lifestyle. Regular examinations by a gynecologist and an orderly sex life are the best methods of prevention.
According to medical statistics, bacteria in the urine during pregnancy are found in every fifth woman. Timely diagnosis and treatment allow for successful treatment of bacteriuria.
Prognosis of bacteria in urine during pregnancy
The prognosis of bacteria in urine during pregnancy depends on when the pathology was detected. If bacteria were detected in the early stages, the prognosis is favorable, since doctors prescribe treatment that prevents the threat of miscarriage. With bacteriuria in the last months of pregnancy, the prognosis depends on the type of bacterial infection and its cause.
If bacteria appeared due to exacerbation of chronic diseases or physiological characteristics of the body, then the expectant mother is prescribed supportive therapy and the prognosis for bacteria in the urine is favorable. But if a woman does not treat bacteriuria, this can cause serious consequences. With bacteria and urethritis, the prognosis depends on early diagnosis and treatment. The earlier the disease is detected, the better the prognosis, even with purulent and gonorrheal urethritis.
Bacteria in urine during pregnancy is a problem that requires special attention and treatment. Timely diagnosis and therapy are the key to the health of the expectant mother and her child.