What should I pay attention to when taking a blood test for pregnancy?

Pregnant mothers can check whether they are pregnant through B-ultrasound, or through blood test. So, can pregnancy be checked only by blood test? Are there any disadvantages to blood tests? Before drawing blood, the doctor may tell the person who needs blood drawn not to eat or drink less water. This is because eating and drinking can affect the final blood draw results. Some people are not pregnant, but are found to be pregnant when having their blood drawn. What is going on?

Blood tests usually involve venous blood. Except for items with special requirements, venous blood tests are generally required to be drawn in the morning. Before blood drawing, try to reduce the amount of exercise, do not eat food, and keep an empty stomach. You can drink a small amount of water, except for some tests that must be taken on time, which will interfere with the results. If you are an inpatient, your blood should be drawn by a doctor or nurse when you are in a relatively stable state. The skin at the blood drawing site should be as clean as possible before blood drawing. The amount of blood drawn is determined by the content of the test and the number of items. The amount of blood drawn is generally 2-20 ml and will not exceed 50 ml at most.

You should fast after 8 pm the night before blood drawing: avoid drinking excessive amounts of alcohol, as the alcohol content in the blood will directly cause the results to increase or decrease; before having blood drawn to check blood lipids, it is best not to eat foods that are too high in fat, such as shabu-shabu, braised pork, etc.; before checking cholesterol, eat less eggs, as these will affect the composition of the blood and cause "misjudgment."

You should get enough sleep the night before blood collection and avoid strenuous exercise in the morning. Because strenuous exercise can temporarily increase the levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), etc., and can also cause changes in blood components such as potassium, sodium, and blood sugar, affecting the measurement results.

On the day of blood collection, do not wear clothes with sleeves that are too tight or too small. Otherwise, the sleeves will be too tight and you will not be able to roll up your sleeves when blood is drawn, or it will be difficult to stop the bleeding, causing hematoma in your arm. At present, everyone is wearing a lot of clothes, so it is best to take off your outer clothes and thick sweaters before drawing blood.

You cannot eat before having blood drawn. Some foods may cause the blood draw results to show pregnancy, so everyone should be more careful when having blood drawn. People who are found to be pregnant during a blood test can go to the hospital for another check-up with a more accurate test to see if they are really pregnant. After all, there are still disadvantages to detecting pregnancy through a blood test.