Pregnancy Test
Am I Pregnant? Testing Guidelines

Pregnancy Testing

- Home Pregnancy Kits
- Meaning of Faint Lines
- Negative Results

Pregnancy Test


Testing For Pregnancy
Home Pregnancy Testing Kits
Can Anything Affect The Results?
Can a Doctor Test Me?
How Soon Can I Test?
My Test Shows a Faint Line. Am I Pregnant?
I Feel Pregnant But My Test Result Is Negative.
Do Online Tests Work?
What Else Can Cause a Missed Period?

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Pregnancy Guide

Testing For Pregnancy

Usually one of first early signs of pregnancy is a missed period. Yet missed or irregular periods must be looked at within the terms of what is normal for you. Most women start their menstruation cycle between the age of 11 and 13, and often it takes years for the hormones that control cycles to regulate. If your periods have been irregular, then a missed period does not necessarily indicate pregnancy. However, if your cycle has been regular, you have had sexual intercourse and your period is late, then pregnancy is more likely. The only way to know for sure is to take a pregnancy test.

Home Pregnancy Testing Kits

Home pregnancy tests are easy to use and available in most drug stores. Clear Blue and First Response are perhaps two of the best known. Most tests can be used on the first day of your missed period, although some brands offer results a few days before this. Accuracy is usual better the closer you are to the first day of your missed period. All home pregnancy tests work by detecting the level of HCG (human chorionic gonadotropin) in the urine; this hormone is normally only produced by a developing placenta. HCG, also known as the pregnancy hormone, finds its way into the bloodstream and urine within 6-12 days after conception. Home pregnancy kits are not usually sensitive enough to pick up signs of HCG in the first week after conception, so if you take a test during this time you are likely to get a negative result, even if you are pregnant. Most tests are 60 percent accurate 4 days before a missed period. This increases to 90 percent on the day your period is due and 97 percent a week later. If you are hoping for a baby, the good news is that a false positive is very uncommon. In other words, if you get a positive result at any stage, you can be fairly certain you are pregnant. To carry out a test, it is important to follow the instructions on your particular pregnancy kit. Nearly all brands involve urinating on a test stick that has been treated with a chemical which reacts to HCG. It is best to carry out your test first thing in the morning before drinking any liquids as levels of HCG will be more concentrated and more easily detected.

Can Anything Affect The Results?

Yes. Although false positive results (where you test positive but are not pregnant) are uncommon, it can happen. Factors which can cause a false positive test result include:

1. Fertility drugs - some infertility therapies include dosages of HCG. A woman who has been given a HCG injection as part of an infertility program will test positive for pregnancy, even when not pregnant.

2. Some diseases including certain forms of cancer like ovary cancer, cancer of the lungs, liver and stomach can all cause high levels of HCG.

3. Smoking marijuana can also increase levels.

Can a Doctor Test Me?

Absolutely. Most doctors, OB/GYNs and clinics use urine tests to confirm pregnancy and follow this up with a pelvic examination. There are also two types of blood tests which your doctor may mention:
A qualitative HCG blood test: Confirms if the pregnancy hormone is present. It gives you a Yes or No answer to the question are you pregnant. It is slightly more accurate than a urine test, and can return 100 percent accurate results as early as 2 weeks after conception. This may even be slightly before your period is due.
A quantitative blood test: Measures the exact amount of HCG present in the bloodstream. Values of HCG change predictably as a pregnancy progresses so this means the doctor can also work out your pregnancy due date. Ultimately if you do not want this test, all will be revealed with your first pregnancy ultrasound scan. Today, given the accuracy of home tests, blood tests are only usually performed in specific cases where an accurate diagnosis of pregnancy is really necessary - for example where the woman is showing spotting and severe tummy pain.

Early diagnosis of pregnancy is good because the sooner you know if you are pregnant, the sooner you can start taking care of yourself.

How Soon Can I Test?

If you are using a home pregnancy kit (e.g. Clear Blue & First Response), then you will need to wait until your period is due, although some kits can predict a few days beforehand. If your period does not arrive, then test the first day after it is due. The only way to know before this is to ask your doctor to perform a blood test. This can return an almost 100 percent accurate result as early as 2 weeks after conception. You can also check to see if you have any of the early signs of pregnancy. Useful additional information, read about: pregnancy questions.

My Pregnancy Test Shows a Faint Line. Am I Pregnant?

The short answer is probably YES. The only way a pregnancy test can give you a positive result is if it detects the pregnancy hormone HCG in your urine. If there is a faint line, this means it is detecting HCG. As to why the line is faint instead of clear and solid may be more to do with the test you used and how far along in pregnancy you are. Some pregnancy tests are more sensitive than others. To check your testing kit, look for the milli-international units per liter (mIU/L) measurement. The lower the number (around 20 mIU/L), the more sensitive the test and the sooner it will be able to tell you if you are pregnant or not (less sensitive kits measure around 50 mIU/L). Also, keep in mind that the more along you are in pregnancy, the higher the levels of HCG and the more easily it is detected. Conversely, the newer the conception, the less HCG present in your system and the 'fainter' the results. See also, what is a chemical pregnancy?.

Table Below: Comparing the main home pregnancy tests.

Pregnancy Test Brand mIU/L (The lower the number, the sooner it can tell if you are pregnant)
AimStick Pregnancy Test Strip 20
Answer Early Result Pregnancy Test 25
Clearblue +/- 25
First Response Early Result 25
Walgreen Digital 25
Confirm 1-Step 25
Clearblue Digital 40
CVS Cartridge 50
Wal-Mart own brand 50
Walgreens own brand 100

You may have experienced a chemical pregnancy. This is a pregnancy that ends before it really takes root. The egg is fertilized and begins to implant in the uterus, but for some reason does not complete implantation. It is estimated that up to 70 percent of all conceptions are chemical, and before home pregnancy testing kits, women simply did not know that they had experienced a brief pregnancy. If you are trying for a baby and are disappointed, remember: if you can conceive once, then you can do so again. See also, is it possible to be a little bit pregnant?

I Feel Pregnant But My Test Result Is Negative

If you are experiencing pregnancy symptoms but your test is negative, then act as though you are pregnant (follow our prenatal care guide). Pregnancy tests are not 100 percent infallible, particularly if taken too early. So wait a few days, and then take a pregnancy test again. If you still have a negative result, but have missed your period, see your doctor. If you continue to test negative, your doctor will be able to rule out other possible biological causes of your symptoms. Sometimes, the mind can play powerful tricks on the body, even creating phantom pregnancy symptoms. This is more likely if the woman is really anxious to become a mother soon.

Do Online Tests Work?

No, is the simple answer! What they may do, is guess the probability of pregnancy by asking you questions about your menstrual cycle, when you last had sex, use of birth control and the presence of any pregnancy symptoms. Any website that offers to remotely scan you for a fee, is not a serious site. The only way to determine with any accuracy if you are pregnant is to carry out a pregnancy test.

What Else Can Cause A Missed Period?

The most common cause for missed periods is pregnancy. However, if you have tested negative for pregnancy, there are other possible causes:
Extreme Weight Gain or Loss: Although a low body weight is a common cause of irregular periods or missed menstrual cycles (in particular for those who suffer from anorexia or bulimia), obesity can also cause problems with cycles.
Excessive Exercise: Missed periods are quite common with female athletes.
Stress: Causes all sorts of problems with the body's hormone and chemical balance.
Illness: A severe illness or operation, in particular if weight loss is experienced, can cause interruptions to the body's natural menstrual cycle.
The Contraceptive Pill: If you have started taking a birth control pill, or changed your brand, this may cause lighter bleeds than normal or even skipped periods. This usually corrects itself within 3 months. See also, how long does it take to get pregnant after stopping the pill?
Female Health Disorders: Such as polycystic ovary syndrome (PCOS), endometriosis, uterine fibroids or an imperforate hymen may have side effects.

See also: our guide to paternity testing for determining who the father is.

Other Interesting Questions
What Are The Early Signs Of Pregnancy Before A Missed Period?
What Tests Do You Need During Pregnancy?

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For more information on preparing for a baby, see the following:

Morning Sickness - Causes, symptoms and natural remedies.
Pregnancy Cravings - Craving weird things like soap and dirt?
Flu During Pregnancy - Which medications are safe.

Return to homepage: Womens Health Advice

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