Your baby this week
4 weeks pregnant

In the know

It's probably still too early to take a home pregnancy test, as tempting as the idea might be! Don't waste your money -- or dash your hopes -- by testing too soon. The forming placenta -- if, indeed, you are pregnant -- just hasn't created enough hCG to be detected yet. Consider this the first of many tests of your patience... and come read Days in waiting: The wait to take a pregnancy test for a look at the "two week wait."

Pregnancy test

Put it out

No smoking

Did you know that quitting smoking now has a tremendous positive effect on not only your health, but the health of your unborn baby? Nicotine is known the constrict the blood vessels, and, therefore, can lead to a decreased blood and oxygen supply from the placenta to the baby. A lot of smokers have premature labor, premature rupture of membranes (PROM), and small for gestational age infants.

After the baby is born, you will not want to be smoking around him or her. Secondhand smoke has been shown to increase chances of many diseases and problems, such as asthma, in children. Click here for more info!

Is it true?!

How accurate are home pregnancy tests? According to U.S. Pharmacist, "False-positive results can occur from a recent birth or miscarriage, due to HCG levels still present in the urine. A false-positive reading could also result from an elevation in the hormone LH (usually 100-1000 IU/L) or certain medications, namely methadone, chlordiazepoxide, or promethazine. Proteinuria or hemoglobinuria also could potentially cause a false-positive result. Since commercially available testing kits now utilize monoclonal antibody technology, these tests are much less susceptible to interference from other substances than were the earlier, hemagglutination inhibition-based tests."

Come back tomorrow to read about false-negative results, or get the scoop now about pregnancy tests, such as how they work and when to test.

Tips & tricks

A quick way to estimate your due date: add seven to the date of your LMP (last menstrual period), subtract three months, then add a year. Easier still -- use our Due Date Calculator!

Ideas & inspiration

Are you ready to be a parent? You are expecting your first child and before you know it you will be holding your little baby snugly in your arms. Then what? After about nine months in anticipation, new parents are often faced with a big surprise. Their baby is not just a baby but a human being with his own personality. He is not someone they can mold entirely. He has his own ways -- already -- of expressing his needs and desires -- and many new moms and dads just aren't prepared for that.

Young couple

T Berry Brazelton, internationally-known pediatrician and child development expert, shares some thoughts to help parents prepare for one of the biggest changes of their lives. Read here to learn more.

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