TUESDAY, Sept. 28 (HealthDay News) -- While some research has linked abortion to the development of mental health problems, a small new study says teenagers who undergo the procedure aren't more likely to be depressed and have low self-esteem than other pregnant teens.

But a researcher who believes having an abortion boosts the risk of mental health problems said the study is too small to reach any reliable conclusions because it looked at just 69 adolescents who had abortions.

Both sides of the abortion debate have seized on recent research into the emotional effects of abortion. In the new study, researchers from Oregon State University and the University of California, San Francisco examined statistics from the National Longitudinal Study of Adolescent Health. Specifically, the researchers looked at responses from 269 adolescent girls who were in grades 7 to 12 from 1994-1995.

The researchers compared 69 pregnant teens who had an abortion to 220 pregnant teens who didn't have the procedure. For the study, the investigators used standard measures of depression and self-esteem, and looked at the participants' mental health before and during pregnancy, as well as one year and five years later.

The findings were released online in advance of publication in the December print issue of the journal Perspectives on Sexual and Reproductive Health, published by the Guttmacher Institute, a nonprofit group that monitors state abortion policies.

In a news release provided by Oregon State University, study lead author Jocelyn Warren, a post-doctoral research associate at the university, said researchers already know that pregnancy boosts depression and low self-esteem in teens. "We know most teen pregnancies are not wanted pregnancies and an unwanted pregnancy can be very stressful," Warren said. "What we didn't know was whether psychological outcomes are worse for girls who choose abortion. This study says, 'No.' "

But Priscilla K. Coleman, professor of human development and family studies at Bowling Green State University in Ohio, said in an interview that many other studies have found the reverse, including some that looked at teens. Coleman said about 10 percent to 20 percent of women who have abortions "are seriously negatively affected."

"The data show that some women are traumatized," Coleman said. "It can be a life-changing negative decision for a lot of women. They deserve up front to know what the risks are."

Warren added that while it is true that individual women may respond very differently to having had an abortion, "on average, abortion does not appear to have major psychological consequences -- for adult women or for teens."

More information

The U.S. National Library of Medicine has more on abortion.