Dear Si_elsis,

No. Fertilization doesn't happen the instant a couple has intercourse — it can actually take up to seven days after sex for the sperm and egg to join and form a fertilized egg. Then, it can take up to eight days, or more, for the fertilized egg to attach itself to the lining of the uterus. Pregnancy begins when this happens.

The only way to be sure of a pregnancy is to take a pregnancy test. If a woman is wondering if she might be pregnant, she can take a home pregnancy test or go to a health clinic for confidential testing. Women who use home pregnancy tests need to be sure to follow exactly the directions on the package.

Hope this information helps!

Take care,

teenwire.com^® Editors

This column is for informational purposes only and is not intended to constitute medical advice, diagnosis, or treatment. If you have a medical problem, please call toll-free 1-800-230-PLAN for an appointment with the Planned Parenthood health center nearest you.