Urinalysis in pregnancy
L'urinalysis in pregnancy it is done every month: it is the exam that is performed most frequently during the nine months, as it provides information on the state of health of the woman, for example, it allows to detect urinary infections or to monitor pathologies such as gestational diabetes and preeclampsia, complications important aspects of pregnancy.
In this article
- Cost of urine tests in pregnancy
- How do you read the report?
- Chemical-physical examination
- The sediment analysis
- Urine culture: when is it done?
- How to properly collect urine
Cost of urine tests in pregnancy
The urinalysis is free if it is carried out in public facilities or structures affiliated with the National Health Service. To obtain the exemption, the doctor must indicate the exemption code for pregnancy in the recipe book.
How do you read the report?
The report is divided into two parts: the chemical-physical examination of the urine and the microscopic examination of the sediment that settles on the bottom of the tube after centrifugation.
The values are interrelated and the individual information must be interpreted in the context of the report.
Here are the items that appear in the chemical-physical examination.
- Specific gravity or density. It is a good indicator of kidney function. Its value is determined by the presence of urea, proteins and glucose. A normal value, between 1010 and 1030, indicates that the kidney is able to perform its functions and to discharge all waste substances into the urine.
- pH. PH is the measure of the acidity or alkalinity of a solution. Normal values range from approximately 5 to 7. "A pH greater than 7 could be caused by a bacterial infection, while a pH below 5 indicates acidosis, which may be due to diabetes mellitus or a diet that is too rich in protein" explains gynecologist Rossana.
- Appearance. The normal appearance of the urine is clear. A cloudy appearance could be due to the presence of mucus or bacteria, due to infections. But a more charged urine can also indicate that you are not drinking enough, for example if the expectant mother suffers from nausea and does not drink in adequate quantities.
- Color. Urine color normally varies between pale yellow and amber. Variations in color from red to blue can be caused by taking medications or dyes; a red / pink color can be determined by the presence of hemoglobin (which in this case will be present), but also, more simply, by the fact that the night before she had a feast of red cabbage, blueberries or candies with red dyes!
- Nitrite. They are usually absent, although small quantities of food-borne nitrites are physiologically excreted with the urine, as well as with sweat and tears. If present in high concentration, they can signal an infection, especially if they are associated with a cloudy appearance and a pH higher than 7.
- Chetonic bodies. They are chemical compounds formed by the degradation of proteins. They can be found if there has been a prolonged fast, for example due to nausea, vomiting, fever or stress.
- Bilirubin and urobilinogen. It is a yellow-red substance that is produced by the destruction of red blood cells and is the main pigment present in bile. "Its presence, which gives the urine a dark Marsala color, could be a sign of liver pain, but these are very specific cases and not related to pregnancy," she says.
- Glucose. It is usually absent or present in minimal quantities, less than 10-15 mg / dl. A higher concentration can be a sign that there is a high amount of sugar in the blood, which is partly dispersed in the urine. If glucose is found in quantities above normal, a blood glucose curve should be performed to assess whether there is gestational diabetes.
- Hemoglobin. As a rule, there is no blood in the urine and an amount up to 0,03 mg / l is considered tolerable. "The presence of blood in the urine can be determined by a cystitis, a cervical polyp, a 'sore' or a bit of gravel (small grains of saline substances produced by the kidney), which can scrape the ureter causing small blood losses" says the gynecologist.
- Protein or albumin. During pregnancy they are one of the most important values of the urinalysis, because the presence of proteins is one of the signs of preeclampsia, together with a blood pressure higher than 140 maximum and 90 minimum and an increase in the amount of fluids in the tissues. In addition to the monthly urine tests, the protein-only measurement can also be performed in the hospital with a stick, which allows a quick check in case of doubt.
"In pregnancy, a slight increase in proteins is considered normal and for this reason, if outside pregnancy the normal limit is set at 150 mg / l, in the nine months a presence of up to 300 mg / l is tolerated.Read also: High bilirubin
The sediment analysis
The sediment is analyzed under a microscope. Here is what you can find.
- Leukocytes or white blood cells. Values considered normal must be less than 5-10 / ml; an increase is the generic sign of an infection.
- Erythrocytes or emesis. They can be found if the presence of hemoglobin is detected in the chemical-physical examination.
- Lower pathway cells, epithelial cells. The presence of few epithelial cells in the urine is due to the normal cell turnover of the inner wall that lines the urinary tract.
- Cristalli. They are often found in the urine even in the absence of pathologies. The most common are amorphous phosphates, calcium phosphate, calcium carbonate, uric acid, calcium oxalates. They mostly depend on the diet of the night before, rich in cheese or meat.
- Bacteria and fungi. Under normal conditions, urine is sterile. If there are bacteria or fungi (commonly called fungi) associated with white blood cells, there is probably an upper or lower urinary tract infection. In this case, the examination will be supplemented by a urine culture.
Urine culture: when is it done?
In addition to the urinalysis, the doctor may request a urine culture if the woman reports burning when urinating or an urge to urinate often, possible signs of infection, or if the urine test reveals values that indicate an infection. With urine culture the 'guilty' germ is identified and with the antibiogram, carried out automatically if the urine culture is positive, the most suitable antibiotic to counteract it is identified.
How to properly collect urine
La urine collection it is always done in the morning, when there is a greater concentration of dissolved substances and therefore the analysis is more significant. It is not necessary to fast, while it is important to first perform the intimate hygiene and discard the first jet of urine, which are those stagnating in the urethra and therefore more in contact with the outside.
The sample taken must be brought to the laboratory within 2 hours, in order not to degrade or alter the substances or multiply the bacteria. If a longer time is foreseen, it is advisable to keep it in the fridge or to collect it when it arrives in the laboratory.
- urine tests
- pregnancy test