Why is the time of blood sampling important?

Blood sampling should be scheduled for the morning or early afternoon. This makes it easier to maintain a fasting state and, more importantly, many reference ranges are based on morning or early afternoon values. In addition, many hormones fluctuate throughout the day, and in such cases, the morning or mid-morning provides the most informative results. Repeat or follow-up tests are easier to interpret if the blood is drawn at the same time as previous tests.

For testing the female hormone system, certain tests and test packages are tailored to specific days of the menstrual cycle.

Where should we have the test done?

In the European Union, laboratories can only operate with an official license, so results are reliable regardless of where the test is performed. However, if you are monitoring changes in a value that reflects a health condition, you should always return to the same laboratory. This is because different laboratories may use different technologies, reagents, thresholds, or even units of measurement, making it more difficult to compare results from different locations.

To eat or not to eat?

Many people know it is important to have an empty stomach when having blood sugar tested. Eating can also affect other parameters, as blood lipid levels rise after a meal, potentially interfering with certain light-based measurement methods. The reference values for most laboratory parameters are based on fasting measurements.

How long before a blood test should I avoid eating?

It is recommended to fast for 12 hours before the test. If possible, have only a light dinner the night before.

Can I drink?

Yes. People of average build are specifically advised to drink about 3 deciliters of water—either tap water or still mineral water. Avoid tea, coffee, soft drinks, or fruit juice. It is also recommended to refrain from drinking alcoholic beverages in the days leading up to the test.

Should I go for a blood test if I am sick?

If you have an acute illness (e.g., a cold), it is recommended to postpone the test. If postponement is not possible, be sure to inform the blood collection staff and your doctor. This is important because some parameters are very sensitive and may respond to even a mild viral infection, which must be considered when interpreting results.

Should I take my medication before the blood test?

Some medications are important to take in the morning and should not be skipped. Always inform the blood collection staff and your doctor if you have taken any medication. If the medication can be postponed, it is preferable to take it after the test.

How does exercise or physical work affect blood sampling?

If possible, avoid strenuous physical activity in the days before blood sampling. If this is not possible, inform the blood collection staff and your doctor, as it may affect certain results.

What are the rules for urine testing?

You will need a sterile sampling container to avoid contamination of the urine, which can be purchased if necessary. The sample should be taken from the first urine of the morning. An evening shower is generally sufficient for proper hygiene. In the morning, you may wash with clean water if you want to be certain. Unless absolutely necessary, avoid providing a urine sample during menstruation. If unavoidable, inform the sample collection staff and your doctor.

What is midstream urine sampling?

It is recommended to discard the first third of the urine from the bladder, collect the middle third in the sample container, and discard the remainder. The middle portion is usually sufficient for testing.

Is there anything else to keep in mind for a stress blood sugar test?

Avoid strenuous physical activity the day before the test and aim for a calm, stress-free morning. Drink about 3 deciliters of water before the test. During the intervals of a 3- or 5-point test, avoid stress if possible. Also, do not drink more than 1–1.5 deciliters of water per hour, as excessive water intake can dilute the blood and distort results.