妊娠检查

定义

A pregnancy test measures a hormone in the body called human chorionic gonadotropin (HCG or hCG). HCG is a hormone produced during pregnancy. It appears in the blood 和 urine of pregnant women as early as 10 days after conception.

How the Test is Performed

A pregnancy test is done using blood or urine. There are 2 types of blood tests:

• Qualitative, which measures 是否 the HCG hormone is present
• Quantitative, which measures 有多少 HCG存在

The blood test is done by drawing a single tube of blood 和 sending it to a laboratory. You may wait anywhere from a few hours to more than a day to get the results.

The urine HCG test is most often performed by placing a drop of urine on a prepared chemical strip. It takes 1 to 2 minutes for a result.

For the urine test, you urinate into a cup.

For the blood test, the health care provider uses a needle 和 syringe to draw blood from your vein 放进管子里. Any discomfort you might feel from the blood draw will only last a few seconds.

How the Test will Feel

For the urine test, you urinate into a cup.

For the blood test, the provider uses a needle 和 syringe to draw blood from your vein 放进管子里. Any discomfort you might feel from the blood draw will only last a few seconds.

Why the Test is Performed

This test is done to:

• Determine if you are pregnant
• Diagnose abnormal conditions that can raise HCG levels
• Watch the development of the pregnancy during the first 2 months (quantitative test only)

正常的结果

HCG level rises rapidly during the first trimester of pregnancy 和 then slightly declines.

What Abnormal Results Mean

HCG level should almost double every 48 hours in the beginning of a pregnancy. An HCG level that does not rise appropriately may indicate a problem with your pregnancy. Problems related to an abnormal rising HCG level include 流产 和 ectopic (tubal) pregnancy.

An extremely high level of HCG may suggest a molar pregnancy or more than one fetus, 例如, 双胞胎.

Your provider will discuss the meaning of your HCG level with you.

注意事项

Urine pregnancy tests will only be positive when you have enough HCG in your blood. Most over-the-counter home pregnancy tests will not show that you are pregnant until your expected menstrual cycle is late. Testing before this will often give an inaccurate result. The HCG level is higher if your urine is more concentrated. A good time to test is when you first get up in the morning.

If you think you are pregnant, repeat the pregnancy test at home or at your provider's office.

参考文献

Jeelani R, Bluth MH. Reproductive function 和 pregnancy. In: McPherson RA, Pincus MR, eds. Henry's Clinical Diagnosis 和 Management by Laboratory Methods. 24日艾德. Philadelphia, PA: Elsevier; 2022:chap 26.

Warner EA, Herold AH. Interpreting laboratory tests. In: Rakel RE, Rakel DP, eds. Textbook of Family Medicine. 9日艾德. Philadelphia, PA: Elsevier Saunders; 2016:chap 14.