Pregnancy Test: What, how & when?

You are on this page means either you have missed your periods or you are having early pregnancy symptoms.

Nowadays, the pregnancy tests available in market are almost 98-99% accurate. Accuracy of pregnancy tests depend on when you are taking the test and how you are performing the test.

How does Pregnancy Test Work ?

A pregnancy test is essentially a test to confirm if you are pregnant or not and this is done by testing a hormone called as human chorionic gonadotrophin (hCG) either in blood (after 8 - 10 days of conception) or urine (12-14 days after conception).

What is hCG

The hormone, hCG is also called as pregnancy hormone as it is very unique to pregnancy. The hormone starts producing only after the fertilized egg attaches to the uterus lining, which is also considered as the start of successful pregnancy. The hormone is produced by the placenta.

The hCG hormone is responsible for early pregnancy symptoms like nausea and morning sickness.

The level of hormone keeps increasing till 13-16 weeks of pregnancy, post which it will start declining. This pregnancy hormone is utilised as an indicator for positive pregnancy.

Not just pregnancy, hCG level can help identify pregnancy complications like:

1. Very low hCG level indicate ectopic pregnancy or a threatened miscarriage.

2. Very high level indicate molar pregnancy (abnormal growth of cells)

When to take pregnancy test?

The sensitivity of the test available in market differ from product to product, so read the paper insert for the ideal time for the testing.

The earliest time when the test can be done is usually 14 days from the date of conception which is essentially as soon as you miss your periods.

However, Ideally you should wait till 1 week after missing period for taking pregnancy test at home for more accurate and reliable result.

This way you can be sure to avoid false negative result (getting negative result even if you are pregnant, as hCG level in urine is not enough to be detected by pregnancy test kit) and you can save money by not repeating test again.

Types of Pregnancy test

There are two types of Pregnancy test:

Urine Pregnancy test and Blood Pregnancy test. Urine Pregnancy tests are non-invasive and can be performed at home with ease, where as Blood Pregnancy Tests need to performed if medical facilities under trained professionals and required medical knowledge to interpret the results

1. Urine Test:

This is the most commonly used test usually taken 1 week after missing the period. The test usually involves either

- Inserting the test strip in the urine container or

- Placing few drops on the test strip using eye dropper or

- Placing the test strip in the urine stream.

The result is usually instant, taking around 1-2 minutes for display. The result can vary depending on the product used, in terms of how to read the result.

The result could be:

• A change of color
• A change in marked line
  
• A symbol, such as “ + ” or “ - ” or
  
• The words stating “pregnant” or “not pregnant”
  

2. Blood Test:

The blood test can be performed to detect pregnancy earlier than urine test approx. 8-10 days after ovulation.

The test need a professional to perform it and hence becomes expensive than urine test.

The test is time-taking as compared to urine test.

The blood tests are again of two types:

• Qualitative hCG: The test detects whether hCG is present or not to simply answer whether you are pregnant or not.
• Quantitative hCG: This test actually identifies the exact concentration of hCG in the blood and can be used to detect pregnancy very early on as it can detect very low concentration of hCG as well.
  

Quantitative hCG test will also help to determine the age of pregnancy corresponding to the concentration of hCG.

Also this test can help detect any abnormalities during pregnancy like miscarriage which corresponds to sudden decline in hCG levels.

Pregnancy Test Result

There are only 2 possible outcomes: Positive or Negative

Pregnancy Test Result Positive:

The test could be positive which means you are pregnant irrespective of how faint or dark the line, mark or symbol is.

If you have some doubts you can always repeat the test

Only in some rare cases you can get a false-positive result (i.e. result shows you are pregnant when you actually are not). This may be because of below factors

• When you have blood or protein traces in your urine or you are on some drugs like tranquilizers, anti-convulsants, some drugs for treating anti-fertility and hypnotics.
• Chemical Pregnancy
• Menopause
• Ectopic Pregnancy
• Medical conditions of ovaries such as cysts

Pregnancy Test Result Negative:

If the test result is negative, in general scenario you are not pregnant. If you feel you have some other symptoms of pregnancy it is better to retest after 1 week.

False-negative result (The test result is negative but you can be pregnant), this may occur because of below reasons 

• The test used was expired
• You have performed the test too early
  
• The test performed was not on the first bathroom visit in the morning or you had too much fluids before testing which can dilute hCG level in urine.
  
• The instructions for the test was not followed as per the insert.
  
• You are on some medications like diuretics or anti-histamines which can alter your reading.
  

If you are not satisfied with the urine pregnancy test results, you can always visit your medical practitioner, who would probably advice for Blood Pregnancy Test which are usually 100% accurate.

If you were planning for a baby and get a negative result, it is best to keep trying. Use Ovulation calculator to know your most fertile days, take 400 mcg of folic acid and eat healthy.

How accurate are the pregnancy tests:

The pregnancy tests are very accurate and reliable in fact they are 98%-99% accurate if used correctly. The pregnancy test works on checking the level of human chorionic gonadotropin hormone (hCG) in urine.

The precautions you can take to make sure the test is accurate are:

Pregnancy tests at home can be so crucial when you dont want to wait for the news any longer. Read more to know how to perform the test correctly. Thanks for reading!!

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