NEW YORK -- U.S. abortions fell 5% during the Great Recession inthe biggest one-year decrease in at least a decade, according togovernment figures released Wednesday.

The reason for the declinewasn't clear, but some experts said it may be due to better use of birthcontrol during tough economic times. Their theory is that some womenbelieve they can't afford to get pregnant.

"They stick to straightand narrow ... and they are more careful about birth control," saidElizabeth Ananat, a Duke University assistant professor of public policyand economics who has researched abortions.

While many stateshave aggressively restricted access to abortion, most of those laws wereadopted in the past two years and are not believed to have played arole in the decline.

Abortions have been dropping slightly overmuch of the past decade. But before this latest report, they seemed tohave leveled off.

The new data from the Centers for DiseaseControl and Prevention found that both the number and rate of abortionsfell 5% in 2009, the most recent statistics available from most states.

Nearlyall states report abortion numbers to the federal government, but it'svoluntary. A few states - including California, which has the largestpopulation and largest number of abortion providers - don't send indata. Experts believe there are more than 1 million abortions performednationwide each year, but because of the incomplete reporting, the CDChad reports of about 785,000 in 2009.

For the sake of consistency,the CDC focused on the numbers from 43 states and two cities - thosethat have been sending in data without interruption for at least 10years. The researchers found that abortions per 1,000 women ofchild-bearing age fell from about 16 in 2008 to roughly 15 in 2009. Thattranslates to nearly 38,000 fewer abortions in one year.

Mississippihad the lowest abortion rate, at 4 per 1,000 women of child-bearingage. The state also had only a couple of abortion providers, and has thenation's highest teen birth rate. New York was highest, with abortionrates roughly eight times higher than Mississippi's. New York is secondonly to California in number of abortion providers.

Nationallysince 2000, the number of reported abortions has dropped overall byabout 6% and the abortion rate has fallen 7%, but the figuresessentially leveled off for a few of those years.

By all accounts, contraception is playing a role in lowering the numbers.

Somecite a government study released earlier this year suggesting thatabout 60% of teenage girls who have sex use the most effective kinds ofcontraception, including the pill and patch. That's up from themid-1990s, when fewer than half were using the best kinds.

Expertsalso pointed to the growing use of IUDs. The IUD, or intrauterinedevice, is a T-shaped plastic sperm-killer that a doctor inserts into awoman's uterus. A Guttmacher Institute study earlier this year showedthat IUD use among sexually active women on birth control rose fromunder 3% in 2002 to more than 8% in 2009.

IUDs essentially prevent "user error," said Rachel Jones, a Guttmacher researcher.

Ananatsaid another factor for the abortion decline may be the growing use ofthe morning-after pill, a form of emergency contraception that has beenincreasingly easier to get. It came onto the market in 1999 and in 2006was approved for non-prescription sale to women 18 and older. In 2009the age was lowered to 17.

Underlying all this may be the economy,which was in recession from December 2007 until June 2009. But wellafterward, polls have shown most Americans remained worried about anemichiring, a depressed housing market and other problems.

You mightthink a bad economy would lead to more abortions by women who arestruggling. However, John Santelli, a Columbia University professor ofpopulation and family health, said: "The economy seems to be having afundamental effect on pregnancies, not abortions."

More findings from the CDC report:

  • The majority of abortions are performed by the eighth week of pregnancy, when the fetus is about the size of a lima bean.
  • White women had the lowest abortion rate, at about 8.5 abortions per 1,000 women of child-bearing age; the rate for black women was about four times that. The rate for Hispanic women was about 19 per 1,000.
  • About 85% of those who got abortions were unmarried.
  • The CDC identified 12 abortion-related deaths in 2009.