What Is a Blood Pregnancy Test and How Does It Work?

Most women discover their pregnancy through home pregnancy tests that rely on urine, but sometimes doctors may request a blood pregnancy test. What is this test? How does it detect pregnancy? And how does it differ from a urine pregnancy test?

What is a Blood Pregnancy Test?

A blood pregnancy test is a diagnostic test conducted to determine whether a woman is pregnant by examining a sample of her blood. 

This test relies on detecting the presence of human chorionic gonadotropin (hCG) hormone in the blood, known as the pregnancy hormone. 

Elevated levels of hCG serve as a sign of pregnancy. Typically, the hormone levels rise rapidly in the first ten weeks after the fertilized egg attaches to the uterine wall.

What are the Types of this Test?

There are two main types of blood pregnancy tests:

• Quantitative Blood Test

This test measures the precise amount of pregnancy hormone in the blood and can provide an estimate of the progression and development of pregnancy. Therefore, it can determine the accurate age of the fetus and assist in diagnosing abnormal pregnancy cases, such as ectopic pregnancies, molar pregnancies, and potential miscarriages. 

This test is conducted to diagnose abnormalities not directly related to pregnancy that cause an elevation in the level of the pregnancy hormone.

• Qualitative Blood Test 

This test only confirms the presence or absence of the pregnancy hormone but cannot determine the exact hormone levels. It is primarily used to confirm or rule out pregnancy.

When Does a Blood Test Detect Pregnancy?

A blood pregnancy test can detect pregnancy 6 - 8 days after fertilization and conception, while a urine pregnancy test can detect pregnancy after 10 days.

Is the Blood Test Accurate?

Yes, the accuracy of a blood pregnancy test is approximately 99%. While urine tests are also accurate, blood tests are more sensitive and can detect lower levels of the pregnancy hormone in the blood.

When a Blood Test Is Used?

The urine test is the standard test for most routine pregnancy cases, but the doctor may resort to a blood test if there are pregnancy-related issues, such as:

• Cases of high-risk pregnancies.
• During fertility treatments when urine test results are negative, but menstrual cycles have not occurred.
• To confirm or rule out the possibility of a miscarriage.
• To confirm or rule out a twin pregnancy.
• To diagnose an ectopic pregnancy.
  

How to Prepare for the Test?

The blood pregnancy test does not require any prior preparations, and fasting is not necessary.

How is the Test Conducted?

A healthcare professional uses a small needle to draw a small blood sample, which is then collected in a tube or small vial for analysis. 

The test usually takes less than 5 minutes, and results are available within several hours to a few days.

The Beta-hCG, Quantitative test provided by Blazma reveals the presence of the pregnancy hormone and measures its precise quantity in the blood. All you need to do is to get in touch with us to schedule a blood sample collection. A specialist will come to your address at the appropriate time, collect the blood sample, analyze it, and send the results via text message.

How are the results interpreted?

Qualitative blood test results are either positive, indicating pregnancy, or negative, indicating no pregnancy. 

While the quantitative blood test result is expressed in milli-international units per milliliter (mIU/mL), the normal range for non-pregnant women is less than 5. During pregnancy, the levels increase based on the gestational age as follows:

• 3 weeks: 5 - 72.
• 4 weeks: 10 - 708.
• 5 weeks: 217 - 8,245.
• 6 weeks: 152 - 32,177.
• 7 weeks: 4,059 - 153,767.
• 8 weeks: 31,366 - 149,094.
• 9 weeks: 59,109 - 135,901.
• 10 weeks: 44,186 - 170,409. 

Abnormal hormone levels may indicate the following:

• Higher than normal levels: Multiple pregnancies, molar pregnancy, ovarian cancer, or testicular cancer in men.
• Lower than normal levels during pregnancy: Fetal demise, incomplete miscarriage, or ectopic pregnancy. 

Are there health risks associated with this test?

No, there are no health risks associated with this blood test. Any potential risks are very minor and include:

1. Mild discomfort.
2. Bruising at the needle insertion site.

However, in rare cases, some women may experience excessive bleeding, fainting, or infection as a result of blood withdrawal. 

What are the main differences between blood and urine tests?

Key Differences Between Blood and Urine Pregnancy Tests: