BY MIKE STOBBE

AP Medical Writer

NEW YORK

But there may be a silver lining: The decline in 2011 was just 1 percent--not as sharp a fall-off as the 2 to 3 percent drop seen in other recent years.

"It may be that the effect of the recession is slowly coming to an end," said Carl Haub, a senior demographer with the Population Reference Bureau, a Washington-based research organization.

Most striking in the new report were steep declines in Hispanic birth rates and a new low in teen births. Hispanics have been disproportionately affected by the flagging economy, experts say, and teen birth rates have been falling for 20 years.

Falling births is a relatively new phenomenon in this country. Births had been on the rise since the late 1990s and hit an all-time high of more than 4.3 million in 2007.

But fewer than 4 million births were counted last year--the lowest number since 1998.

Among the people who study this sort of thing, the flagging economy has been seen as the primary explanation. The theory is that many women or couples who are out of work, underemployed or have other money problems feel they can't afford to start a family or add to it.

The economy officially was in a recession from December 2007 until June 2009. But well into 2011, polls show most Americans remained gloomy, citing anemic hiring, a depressed housing market and other factors.

The report by the Centers for Disease Control and Prevention is a first glimpse at 2011 birth certificate data from state health departments.

Highlights of the report include:

The birth rate for single women fell for the third straight year, dropping by 3 percent from 2010 to 2011. The birth rate for married women, however, rose 1 percent.

The birth rate for Hispanic women dropped a whopping 6 percent. But it declined only 2 percent for black women, stayed the same for whites and actually rose a bit for Asian-American and Pacific Islanders.

Birth rates fell again for women in their early 20s, down 5 percent from 2010--the lowest mark for women in that age group since 1940, when comprehensive national birth records were first compiled. For women in their late 20s, birth rates fell 1 percent.

Birth rates held steady for women in their early 30s, and rose for moms ages 35 and older.

Birth rates for teen moms have been falling since 1991 and hit another historic low. The number of teen births last year--about 330,000--was the fewest in one year since 1946.