How to Prepare for Tests

Proper preparation is essential to ensure that laboratory test results are accurate and reliable. Depending on the type of test, requirements may vary — some tests must be performed on an empty stomach, others at a specific point in the menstrual cycle, or with special hygiene precautions. Below you’ll find general guidelines for how to prepare for the most commonly performed tests at our clinic.

Blood tests

Most blood tests should be performed on an empty stomach — approximately 12 hours after the last meal.
For children, a light breakfast may be allowed.
Before the test, do not consume any drinks, especially sweetened beverages or coffee, as they may affect certain results. You may drink a small amount of still water.
Avoid testing after a sleepless night, intense physical exertion, or alcohol consumption the day before.
Taking medications on the day of the test should be discussed with your doctor. Unless otherwise instructed, you may take medications as usual (with a small amount of water).
However, if possible, take your medications after the blood draw — especially dietary supplements and vitamins.
Hormone tests generally do not require fasting, except for prolactin.
If you tend to faint during blood draws, please inform the healthcare provider beforehand — appropriate precautions will be taken.

Urinalysis

Use the first morning urine sample.
Collect the sample immediately after waking, into a clean, disposable container.
Label the container with your full name, date of birth, and the date of sample collection.
Do not collect the sample during menstruation.

Urine culture

Use the first morning urine sample, with specific precautions.
The sample must be collected into a sterile container.
Before collecting the urine, thoroughly wash the genital area using only water (avoid disinfectants).
Collect urine from the midstream (do not collect the first or last portion).
Provide two samples, minimum 20 ml each.
Label both containers with your full name, date of birth, and the exact date and time of sample collection.
Deliver the samples to the lab as soon as possible — within 2 hours at most.

Stool sample

Collect fresh stool from several areas using the spatula included with the container.
Use an amount about the size of a hazelnut.
Avoid contamination with urine or cleaning agents used in the toilet.
Seal the container tightly and label it with your name, date of birth, and the date of sample collection.
Deliver the sample to the lab as soon as possible.
No special diet is required for stool tests for occult blood.
Do not collect a sample during menstruation.

Throat / nasal swab

Collect the sample in the morning, before eating, drinking, or brushing your teeth.
Do not use mouthwash or nasal sprays on the day of the test.
If you have recently taken antibiotics, wait at least 7 days after finishing treatment, unless otherwise instructed by your doctor.
Avoid using decongestant nasal sprays before a nasal swab.

Vaginal / cervical / urethral swab

Perform the test before starting antibiotic treatment or at least 7 days after finishing it.
Avoid using vaginal medications, rinses, or having sexual intercourse for 24 hours before the test.
Do not schedule the test during menstruation.
The best time to perform the test is 2–4 days after your period ends.

Oral glucose tolerance test (OGTT)

Perform the test in the morning, on an empty stomach — at least 8 hours (ideally 10–12 hours) after the last meal.
Remain in the lab for the entire duration of the test (usually 2–3 hours).
Avoid intense physical activity and stress prior to the test.
Consume at least 150 g of carbohydrates per day for 3 days before the test.
Do not smoke, drink coffee, or consume any beverages other than water on the day of the test.

Hormone tests (TSH, FT3, FT4, LH, FSH, Estradiol, Prolactin, etc.)

Most hormone tests can be performed regardless of food intake, except prolactin, which requires fasting.
It is recommended to perform hormone tests in the morning hours, preferably between 7:00 AM and 10:00 AM.
For tests related to the menstrual cycle (e.g. FSH, LH, Estradiol), it’s important to collect the sample on the appropriate cycle day — as advised by your physician.

Faecal occult blood test (FOBT)

No special diet is required.
Do not collect a sample during menstruation or when experiencing visible rectal bleeding (e.g. from hemorrhoids).
If you are taking blood-thinning medications, consult your doctor before testing.