Mayo Clinic Health Manager
Get free personalized health guidance for you and your family.
Get Started
About our e-newsletters
- Free e-newsletters
- Mayo Clinic expertise
- We do not share your e-mail address
Housecall, our weekly general-interest e-newsletter, keeps you up to date on a wide variety of health topics with timely, reliable, practical information, recipes, blogs, questions and answers with Mayo Clinic experts and more. Our biweekly topic-specific e-newsletters also include blogs, questions and answers with Mayo Clinic experts, and other useful information that will help you manage your health.
Housecall Archives
Mayo Clinic Housecall
Stay up to date on the latest health information.
What you get
- Free weekly e-newsletter
- Mayo Clinic expertise
- Recipes, tools and other helpful information
- We do not share your e-mail address
Causes
By Mayo Clinic staff
How the heart works
The heart is divided into four hollow chambers, two on the right and two on the left. In performing its basic job — pumping blood throughout the body — the heart uses its left and right sides for different tasks. The right side of the heart moves blood to the lungs through vessels called pulmonary arteries. In the lungs, blood picks up oxygen then returns to the heart's left side through the pulmonary veins. The left side of the heart then pumps the blood through the aorta and out to the rest of the body.
How heart defects develop
A baby's heart starts beating just 22 days after conception. At that point, the heart has a simple tube shape. Between days 22 and 24, the heart begins to bend to the right and fold in on itself to form a loop. By 28 days after conception, the tube has a vaguely heart-like shape with structures corresponding to the heart's two sides and the large blood vessels that carry blood in and out of them.
It's usually at this point in your baby's development that heart defects may begin to develop. Researchers aren't sure exactly what causes defects to begin, but they think some medical conditions, medications and genetics may play a role.
- Congenital heart defects. National Heart Lung and Blood Institute. http://www.nhlbi.nih.gov/health/dci/Diseases/chd/chd_all.html. Accessed Sept. 8, 2008.
- Congenital heart defects in children fact sheet. American Heart Association. http://www.americanheart.org/presenter.jhtml?identifier=12012. Accessed Sept. 8, 2008.
- Diabetes and pregnancy frequently asked questions. Centers for Disease Control and Prevention. http://www.cdc.gov/ncbddd/bd/diabetespregnancyfaqs.htm#whatcanhappentoababy. Accessed Sept. 18, 2008.
