New data released in the United States shows that birth rates in the country have declined for a third year in a row.

The U.S. Center for Disease Control and Prevention says its provisional count of births in the United States for 2010 was just over 4 million.

That is down 3 percent from the number of births in 2009.

The count has been dropping since 2007 when births hit an all-time high in the United States of more than 4.3 million. Before 2007, births had been on the rise for years.

The report is the first glimpse of 2010 birth numbers from state health departments. It does not include an actual review of birth certificates which will be part of the CDC's final report.

The CDC did not say why the birth rate might be falling in the United States.