Pregnancy Tests - What They Are & How They Work

If you have missed your period or are experiencing the early signs of pregnancy, it is time to conclusively determine if you are pregnant or not. A visit to your doctor’s office should entail the following:

  1. The doctor will ask you questions about your previous menstrual cycles and also about your medical history.
  2. They will prescribe a lab evaluation involving your blood and urine samples.
  3. If required at this stage of your pregnancy, they may prescribe an ultrasonography.

During pregnancy, your body secretes certain hormones that can be used as markers to confirm the pregnancy. Human Chorionic Gonadotropin (HCG) is one such marker that has been extensively used to diagnose pregnancy. HCG is produced by special cells of your fertilized eggs after the fetus is firmly implanted in the uterus. HCG is a reliable marker of pregnancy but testing for HCG can often result in false negatives during the early stages of pregnancy.

These days home pregnancy kits are very easily available in the market, letting you confirm if you are pregnant from the comfort of your home. They come with clear and precise instructions on the back of the pack, making them very easy to use. These tests can usually verify the status of your pregnancy. A blood test might take longer to confirm your pregnancy, but it is the most accurate method.

While urine tests can be performed at home, blood tests are done at labs. Blood tests simply check the levels of HCG and give clear results. HCG is detectable in the blood of approximately 5% of patients 8 days after conception and in more than 98% of patients after 11 days. The initial rate of rise, measured by serial quantitative HCG testing, is important in the monitoring of complications early in the pregnancies.

There is a chance that you might get wrong results i.e., a false positive or a false negative, from both laboratory tests and at-home-pregnancy tests. It is always best to be well informed. While both the tests confirm pregnancy, blood tests are generally more accurate. Studies have also revealed that many users fail to understand or follow the instructions in the home pregnancy test kits, resulting in unreliable results. Reading the instructions carefully and following them step by step is extremely crucial. 

The Level Of Accuracy Of A Home Pregnancy Test Kit Depends Upon Various Things Such As:

  1. How closely you follow instructions.
  2. When you ovulate in your cycle and how soon implantation occurs.
  3. How soon after pregnancy you take the test.
  4. The sensitivity of the pregnancy test.

Testing too early can lead to the test giving out false-negative results. Most doctors recommend that you wait until the first day of your missed period before taking a urine pregnancy test. This is usually about two weeks after conception.

While false negatives are very common, false positives are also not unheard of. They usually occur due to incorrect usage, consumption of certain drugs containing the HCG molecule, and the production of the HCG molecule that occurs in some tumours. A woman who has been given an HCG injection due to infertility treatment will also test positive on pregnancy tests, regardless of her actual pregnancy status.

Close coordination with your doctor can help you sail effortlessly through these tests and can also help you enjoy your pregnancy.

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