Teen pregnancy rates are highest in New Mexico and lowest in New Hampshire, according to a new report on the most current state-level data on pregnancy, birthrates and abortions among 15- to 19-year-olds.
The data is from 2008, the most current year that comprehensive information is available, according to the reproductive rights agency the Guttmacher Institute. Though 16 states did see an increase in teen pregnancies between 2005 and 2008, the analysis suggests that overall rates are continuing their decades-long decline.
"There are a few key factors driving the long-term declines in teen pregnancies," Guttmacher senior researcher Laura Lindberg said in a statement. "It is now the norm for teens to use contraceptives at first sex, which creates a pattern of continued contraceptive use down the road. Additionally, teens increasingly use the most effective birth-control methods, including hormonal methods and long-acting contraceptive methods like the IUD. By contrast, there has been less change in teens' levels of sexual activity."
IUDs, or intrauterine devices, are small t-shaped devices that are inserted into the uterus to prevent pregnancy. They have a low failure rate and last for between five and 10 years, depending on the type.
Nationwide statistics revealed in 2012 that the teen pregnancy rate hit a 40-year low in 2008. In 2008, the national teen pregnancy rate was 68 pregnancies per 1,000 teens, a 42 percent decline from the peak rate of 117 pregnancies per 1,000 teens in 1990.
With lower pregnancy rates, abortion rates dropped, too. In 2008, the teen abortion rate hit 17.8 abortions per 1,000 women, the lowest since the legalization of abortion in 1973.
State-by-state data is harder to come by, which is why the latest report comes out a year after the nationwide data. The results suggest that while the overall picture is positive, a teen's chances of becoming pregnant vary widely from state to state.
The highest pregnancy rate as of 2008 was in New Mexico, where 93 out of 1,000 teens became pregnant. Mississippi, Texas, Nevada, Arkansas and Arizona rounded out the top six states for teen pregnancy.
In the lowest-ranked state, New Hampshire, only 33 out of 1,000 teens became pregnant, the data revealed. Vermont, Minnesota, North Dakota and Massachusetts followed with similarly low rates. [See List of State-by-State Teen Pregnancy Rankings]
Because of abortion and miscarriage, pregnancies don't always result in birth. The highest teen birthrate in the country was in Mississippi, where 55 out of 1,000 teens became mothers in 2010. (Birthrate data is available more quickly than overall pregnancy data, so these statistics are more current.) The lowest teen birthrate was in New Hampshire, with 16 out of 1,000 births per teen.
The teen abortion rate was highest in New York, with 37 abortions per 1,000 teen women in 2008. It was lowest in South Dakota, where five out of every 1,000 teens got an abortion that year.
Teen pregnancy rates declined in every state between 1988 and 2005, a trend that did not hold between 2005 and 2008. Sixteen states saw an increase in the teen pregnancy rate of 5 percent or more in that timeframe.
Louisiana saw the largest bump, from 67 to 80 pregnancies per 1,000 from 2005 to 2008. However, Guttmacher researchers noted, Hurricane Katrina caused disruptions and an exodus from the state in 2005, making that year's teen pregnancy rate artificially low. Utah's teen pregnancy rate went up by 12 percent between 2005 and 2008, and Pennsylvania's went up by 11 percent. [10 Facts About the Teen Brain]
New Jersey's teen pregnancy rate decreased the most in those three years, dropping 13 percent from 71 to 62 pregnancies per 1,000 teen women. Nevada and Arizona saw the next-biggest drops at 9 percent and 8 percent, respectively.
The increase in teen pregnancies in some states is "troubling," the report's authors wrote, but it may reveal short-term fluctuations rather than long-term trends. Birthrates continued to decline between 2008 and 2010, and the Centers for Disease Control and Prevention reported another drop for teen abortions in 2009, suggesting that teen pregnancy declines are continuing over the long term.
"If abortion rates stay relatively unchanged through 2010, teen pregnancy rates in individual states, like birthrates, will decline," the authors wrote.
The full Guttmacher report, released today (Feb. 25) is available online.
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Stephanie Pappas is a contributing writer for Live Science, covering topics ranging from geoscience to archaeology to the human brain and behavior. She was previously a senior writer for Live Science but is now a freelancer based in Denver, Colorado, and regularly contributes to Scientific American and The Monitor, the monthly magazine of the American Psychological Association. Stephanie received a bachelor's degree in psychology from the University of South Carolina and a graduate certificate in science communication from the University of California, Santa Cruz.