How do Pregnancy Tests Work?

Pregnancy tests identify a special hormone in the blood or urine produced during pregnancy. This hormone is called human chorionic gonadotropin (HCG), often referred to as the pregnancy hormone. There are two basic types of pregnancy tests, blood and urine.

Home pregnancy test are primarily urine tests. These are easy to use, private and inexpensive. Most are quick and very accurate, claiming a 99% accuracy rate. Tests can be purchased at drug and discount stores without a prescription. False positives are very rare, but a false negative is possible if the test is done too early for sufficient quantities of HCG in your urine. False negatives can be avoided by waiting until your period is due, or about 2 weeks after you ovulate. Confirming a negative result with a second test a few days or a week later is wise. Always follow a positive result with a trip to your doctor for confirmation and prenatal care.

Medicines containing HCG can cause a false positive on your home test, but most over-the-counter and prescription drugs will not affect test results.

Blood test results may take a few hours or a day, and usually require a trip to the doctor or lab. There are two types of blood tests for pregnancy. The first, a qualitative HCG blood test, provides simple positive or negative results, similar to a urine test. This test is slightly less accurate than the quantitative blood test (or beta HCG test) which measures the exact amount of HCG in the blood. The beta test's ability to pick up small traces of HCG in the blood increase its accuracy.

Whichever type of test you choose, it is important to remember that a follow-up trip to the doctor is important for you and your new baby.

Maria writes for Pregnancy Due Date, a site that tries to information for expectant mothers. For more great pregnancy articles, visit our Pregnancy articles archive.

In The News:


pen paper and inkwell


cat break through


Its Not A Sin For Pregnant Women To Have A Massage

Getting pregnant is really a moment of joy. Don't get... Read More

Delight in Pregnancy Bedrest

My first experience with bedrest was at 30 weeks into... Read More

How to Get Your Pre-pregnancy Body Back

The second biggest question you will ask yourself as a... Read More

How do Pregnancy Tests Work?

Pregnancy tests identify a special hormone in the blood or... Read More

The Myths of Fitness During Pregnancy - The Straight Facts on the ACOG Guidelines

The American College of Obstetics and Gynecology (ACOG) guidelines are... Read More

Pregnancy Exercise

One of the best things you can do to prepare... Read More

How To Eat A Healthy Diet During Pregnancy

Perhaps the number one complaint of women trying to watch... Read More

What Would I Do Without My Doula?

By the time my husband and I finally got pregnant... Read More

Exercising After Pregnancy

Generally most women can begin a formal exercise program within... Read More

10 Pregnancy Risk Factors that Every Pregnant Woman Should be Aware of

Many factors affect the development of a fetus into a... Read More

Life After Birth

LIFE AFTER BIRTH: THE FIRST 6 WEEKSLife after birth can... Read More

Early Signs of Pregnancy

Think you may need to do a home pregnancy test?... Read More

The First Warning Signs of Pregnancy

Pregnancy can be exciting or daunting, depending on the circumstances.... Read More

How To Avoid Swelling When Pregnant

Edema, otherwise known as swelling, will affect almost all women... Read More

How To Prepare For Natural Childbirth

SURROUND YOURSELF WITH PEOPLE WHO BELIEVE THAT BIRTH IS NATURAL,... Read More

Twins Pregnancy?A Father?s Point of View

So you're expecting twins. Congratulations!Are you still in shock? I... Read More

Dealing With Common Pregnancy Complaints

Pregnancy is not without its side effects. During pregnancy your... Read More

How to Deal With Headaches During Pregnancy

Headaches are one of the more unpleasant "side effects" that... Read More

Dietary Precautions During Pregnancy

When you are pregnant, you should be sure to wash... Read More

Is A Baby Allowed To Play In Its First Month?

What should you do to have a happy pregnancy? Many... Read More

The Dos and Donts of Pregnancy

With so many people giving their opinion on what to... Read More

Mommy Is Having A Baby!

Preparing for a new arrival from the beginning of your... Read More

Piece of Mind During Pregnancy - It is Possible with Babysheart

After four years of marriage my husband and I started... Read More

Being Pregnant Is Not a Hurdle to Enjoy A Little Romance

Most of the time pregnant women are afraid to have... Read More

Exclusively Pumping Breast Milk: Why Women Do It

Exclusively pumping breast milk is best thought of as an... Read More

How Fast Will I Lose The Weight I Gained During Pregnancy?

Remember as with any weight loss and exercise program, moderation... Read More

Keeping Cool When Pregnant

Chill Out: how to keep your cool this summerWhen the... Read More

Fetal Development Month by Month

Month 1: Your first month of pregnancy your baby will... Read More

Successful Weight Loss After Pregnancy

How fast you lose weight will depend on a number... Read More

Glutathione for a Healthier Pregnancy

All parents-to-be nurture the dream of a healthy pregnancy and... Read More

Pregnancy and Exercise, How to Stay Fit While Being Pregnant

EXERCISE SAFELYThe first thing to understand when you exercise during... Read More

Abortions After Fetal Viability

Abortion is without a doubt one of the hottest and... Read More

Problems Associated With Teen Pregnancy

Pregnancy is one of the pivotal moments of a woman's... Read More