Pregnancy Test

Pregnancy blood test is required to determine whether or not a woman is pregnant.

Now of course home pregnancy test kits have made sure that it is a simple procedure done in the privacy of one’s home that can accurately determine whether a pregnancy subsists or not.

Pregnancy blood tests are usually undertaken to confirm a pregnancy by detecting or measuring the presence of the hCG hormone in the blood.

A quantitative pregnancy blood test for hCG determines the level of hCG present in the blood stream whereas a qualitative test will offer a simple positive or negative result; whether a woman is pregnant or not.

Though urine tests conducted at home by the woman herself are seen as fairly accurate, they are not as accurate as pregnancy blood tests. This is because there may be a flaw in the test; it could be past its expiry date or it may be used incorrectly or at the incorrect time.

For all these reasons a urine test may show false negatives even in the presence of a pregnancy.

A blood test is more accurate than the urine test because all these possible problems are obviated and also a blood test may be able to detect even lower levels of hCG than would a urine test.

So long as the lab carrying out the pregnancy blood test follows proper protocol and technique and uses the prescribed methodology, a blood test to determine a pregnancy is more accurate than a urine test.

Other than determination of the presence or absence of a pregnancy, blood tests performed during pregnancy will also determine the following:

• A pregnancy blood test will examine what blood type a woman is and also ask what the blood group of the father is. Since the Rh factor in blood types is crucial to a pregnancy this is an important test. When the factor Rh is found to be negative in a woman’s blood type, certain treatments have to be initiated for the protection of the unborn baby from certain blood related problems.
• The pregnancy blood test will also measure a woman’s hemoglobin level, to determine whether or not she is anemic. Anemia can increase the risk of a preterm delivery and also cause a woman to feel even more tired than normal during her pregnancy. If required, iron supplements will be prescribed.
• A blood test administered during pregnancy will also look for HIV, AIDS, other sexually transmitted diseases or Hepatitis B, because they may be harmful to the baby.
• The pregnancy blood test will also look for antibodies for chickenpox and Rubella. If infected with these diseases during a pregnancy, this could be very serious since it could have consequences such as birth defects in the baby.

These are just some of the routine reasons for which pregnancy blood tests are performed.

If a pregnancy is high risk, if there is the presence of infection or disease, high blood pressure or diabetes, or if it is subsequent on a miscarriage, additional blood or other tests may be prescribed.

The home pregnancy test kit, with its easy accessibility and high degree of reliability has made it possible for women to find out early and accurately the status of a possible pregnancy in the privacy of their own homes.

The home pregnancy test has, over the past few decades empowered women by putting this knowledge into their own hands; the better to be able to control their own destinies.

Prior to the arrival of this device, women had to wait for a doctor to perform a blood test to confirm a pregnancy.

Now this is a simple procedure that women can quickly and conveniently perform at home to get a very accurate answer to their question about pregnancy.

A home pregnancy test kit is something that detects the presence of human chorionic gonadotropin (hCG) in the urine of a pregnant woman.

Elevated levels of hCG in blood or urine indicates the subsistence of the pregnancy.

However, since blood being used for a home test has obvious problems, the simple expedient of collecting a urine sample to test hCG levels is used for the home pregnancy test; which typically requires peeing on a stick so to speak.

These tests are simple to use: they require a few drops of urine, preferably collected from an early morning sample so as to offer a high concentration of hCG.

When placed on the test strip the change in color or will indicate in some other way whether a woman is pregnant or not.

The instructions are simple to follow and clearly printed on the package. The test kits do have the following limitations however:

• The home pregnancy test kits generally available will not be able to detect a pregnancy directly after conception. Most kits will tell you to wait until the first day that you would ordinarily have expected your period to carry out the test. This is because the test depends on the implantation of the embryo into the uterine wall to have been completed before it will show up positive. So when performed too early, this will yield a false negative even when conception has occurred.
• Though laboratory testing has shown a high degree of accuracy in yielding results; when in the hands of actual consumers, this accuracy is considerably reduced; some estimates put the degree of accuracy as low as 75%.
• Improper usage, very early use, or using expired home pregnancy test kits could result in false negatives or false positives as well.
• For those women who have irregular menstrual cycles and unpredictable ovulatory episodes may have inaccurate results. It is not when a woman had intercourse that decides the time of conception, but when ovulation occurred that is material. So, if a woman ovulates late, conception will be late and will not be able to be detected in home pregnancy test.

So while the home pregnancy test kit is a powerful tool not only for convenience but also privacy, it is subject to its limitations.

It is not an uncommon experience that a woman’s period is late and a negative pregnancy test results when it is taken.

• So does a negative pregnancy test indicate?
• Does it always mean that a woman is not pregnant?
• Can there be a negative pregnancy test even when there is a pregnancy subsisting?
• So you are a week late but the negative pregnancy test says you are not pregnant. Whom do you believe and why would something like this happen?

These are confusing questions that we try and simplify here:

Usually speaking, a negative pregnancy test would mean that a woman is not pregnant.

However, when such a negative test is accompanied by symptoms such as a missed or late period, and tiredness, breast tenderness, needing to go the loo more often, morning sickness etc, then it is possible that there may be a pregnancy subsisting.

There are several reasons why a pregnancy test could show up negative even when there is a subsisting pregnancy:

1. One reason could be that the pregnancy test kit that you have bought is a low quality one, or a low sensitivity one. Some test kits are capable of detecting hCG levels only when they reach a certain threshold and not before. So either one’s hCG levels have hot reached that level yet or the brand is a less sensitive one; typically one that asks you to wait until the first day that you would have missed your period.
2. The test may have been taken at a time when the hCG levels of a woman’s urine sample are not at their highest and therefore may yield a false negative. It is important to perform the test using the first morning urine sample when the level of hCG in the urine are their most concentrated.
3. Sometimes a negative pregnancy test could result from a faulty or expired test kit. Always check to see that a test kit is not past its expiry date; beyond which its efficacy will go down.
4. It is also important to make sure that instructions for testing are followed fully. Many may say there’s nothing to peeing on a stick, but things can go wrong. Also wait for the amount of time indicated for the results to develop, don’t be in a hurry to discard the test.
5. While some women could have conceived well before the expected date of a period, others may have conceived just a few days before a period is due. In  the event, those that have conceived a little later in their cycle would have had the embryo implanted late as well and consequently their hCG levels may not be high enough to be detected by a test kit resulting in a false negative pregnancy test result.

Rule out all possible other reasons for a missed period if there is a negative pregnancy test, and remember that pregnancy tests could be negative for all these and yet other reasons.

Though they are accurate 97% of the time, there is still that 3% that we have to factor in!

To understand why you may sometimes end up with a false positive pregnancy test you need to understand how the common or garden variety of home pregnancy test kits work.

The modern pregnancy test has made it a simple matter to confirm a pregnancy by the simple expedient of peeing on a stick.

The test device works by detecting the presence of HCG or human chorionic gonadotropin in the blood or urine of a pregnant woman. The lateral low technology is used for this and if the test is positive, the urine usually changes color and a colored line shows up in the testing strip area.

The home pregnancy testing kit is very reliable and one study showed that when used by experienced technicians, it had an accuracy level of over 97%, the same professional laboratory testing in terms of accuracy.

 In the hand of consumer, however, the accuracy of the test was shown to be about 75% only. This goes to show that they may be a high level of users who do not use the testing device properly or as instructed.

This gives rise to a false positive pregnancy test and equally as well work the other way around; by throwing up a false negative. Improper use and failure to follow instructions is a big reason why a false positive pregnancy test may show up.

Sometimes a particular constituent of one’s urine can give rise to an evaporation line which could be mistaken for a positive result in a test kit. In this case, testing should be done again in a few days to get the correct result.

In rare cases, the testing kit itself may have some anomaly or manufacturing defect or sometimes the expiry date may have passed. So be sure to check the date of manufacture on the package and also the date of expiration because an expired product may not give you correct results.

Certain medications may increase levels of the HCG hormone in the body and may therefore result in a false positive pregnancy test.

Understand that a false positive pregnancy may result from a number of different factors as stated above and also other possible reasons. So it is important to follow instructions fully and correctly.

Make sure that the brand you buy is good quality and well within the date of expiry. Also do not depend on the home test entirely, have the findings confirmed by a doctor’s test for an accurate result.

The common home pregnancy test kit is usually quite fool proof and 99% of the time it will give you a correct reading of the pregnant or non pregnant state of a woman.

However, in some rare cases, a home pregnancy test will display a false positive and there could be several reasons for this:

• Not following directions properly can sometimes result in a false positive result.
• The home test kit is either contaminated or is faulty. On rare occasions there could be something wrong with the strip that you may be using and therefore may show a false positive
• Contamination or impurity of the urine sample. A home test kit usually requires a woman to use a urine sample for taking the test. If the sample is collected in a cup having traces of detergent or if there is some blood in the sample, this could result in a false positive.
• Certain prescription medications can interfere with an accurate result so that if one is on any kind of tranquilizers, diuretics, anticonvulsants etc, there are chances of the test showing a false positive
• Certain medical conditions can cause the test result to show a false positive, particularly if there is a disorder or tumor of some sort in the reproductive tract.