More than one-third of US births between 2006 and 2010 were the result of unintended pregnancies, meaning the overall rate of unintended births has not changed much since 1982.
"We have made no progress since 1982 in reducing the percentage of births that are unintended," said report author William Mosher, a statistician at CDC's National Center for Health Statistics, according to Health Day. "It was 37 percent in 1982, and it's still 37 percent."
Health Day also reported that Mosher said "intended" births are planned, whereas "unintended" births are either "mistimed," meaning they occurred either a short time or years before the mother planned to become pregnant, or "unwanted," meaning the mother did not want the pregnancy, whether or not she already had other children.
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The study, which looked at data from 2006 to 2010, showed that among married women, 23.4 percent of births were unintended, while half of births to unmarried women living with a partner were labeled the same, according to My Health News Daily. Among women who were unmarried and not living with a partner, 66.9 percent of births were unintended, a rate that rose from 2002's 59.5 percent. The highest rate of unintended births was among young women from this same group — 78.9 percent of births to unmarried women aged 15 to 24 were unintended.
Doctors and researchers have said the numbers do not surprise them, but many are discouraged by the lack of improvement in the last three decades, reported ABC News.
"Trying to prevent unintended births is sort of an increasingly difficult task," Mosher said to ABC.