For many years, it’s been widely cited that at least 50% of pregnancies in the US are unplanned. That, however, isn’t true, at least it wasn’t from 2008 to 2011. Unplanned pregnancies have dropped to their lowest level in 30 years, according to researchers at The Guttmacher Institute. Publishing their new study in a March edition of the New England Journal of Medicine, the group found that only 45 out of every 1,000 US pregnancies were unintended in 2011. Three years previous, in 2008, 54 out of every 1,000 pregnancies had been unplanned.

Unintended Pregnancies Decrease Across Demographics

Perhaps more importantly, the decline was observed across almost every demographic, although disparities remain along the lines of income, race, education-level and maternal age. We’ll get into those differences in a moment, but first, note what Dr. Lawrence B. Finer, the study’s lead author, told the New York Times:

“This is the first substantial decline since we’ve been tracking it […] Whereas in the past we saw decreases among advantaged groups but increases among disadvantaged groups, now we’re seeing decreases across the board. Something broad-based is going on here.”

As for the nature of that “something,” Finer and his colleagues don’t think it’s a change in people’s sexual behavior. Reviewing data on teenage sexuality, the researchers saw little change in how many teens reported having sex, and historically, adults rarely change how often they have sex. The country’s changing demographics aren’t a very good explanation either. Many of the very ethnics groups, like people who identify as Hispanic or Latino, that are increasing have relatively high rates of unintended pregnancy.

Contraception & Long-Acting Birth Control

So what’s causing the decrease in unplanned pregnancies? Contraception, Finer thinks. More young couples are opting to use birth control, primarily male condoms, during their first sexual experiences. In 1985, 56% of young women reported using a contraceptive the first time they had sex. By 2004, the number had risen to 76%. In this latest sample, which ended in 2011, 84% of women said they used birth control in their first sexual experience.

Young Woman On Bike

It’s not just contraception use, however, that’s driving the downward shift, researchers say. Just as important is how long those birth control methods are intended to remain effective. The use of intrauterine devices (IUD) is on the rise, especially among women who have already had a child. 8% of women who have had one child now report using an IUD, compared to only 2% in 2002. Another sign that birth control is behind the lower unplanned pregnancy rates? Abortion rates remained relatively stable between 2008 and 2011, rising by only 2%, but the number of unintended pregnancies that went to term, ending in a live birth, went down, from 27 out of every 1,000 in 2008 to 22 out of every 1,000 in 2011.

More women, however, are using emergency contraception, like Plan B, than ever before. In 2002, only 4% of women in a national sample had used the morning-after pill, according to a Centers for Disease Control review. By 2008, around 10%, an estimated 5.2 million American women, had.

Sharp Differences Observed Across Demographics

This recent drop in unintended pregnancies aligns with a historical trend, which saw rates decline modestly over the last three decades, before rising sharply between 2001 and 2008. Finer says its good news, but noted some major differences between different demographics.

Women living below the federal poverty line are still far more likely, anywhere between 2 and 3 times more likely, to experience an unplanned pregnancy than wealthier women. Even so, the rate of unplanned pregnancy among women with incomes at or two-times lower than the poverty line dropped by 32%, the largest decrease of any demographic.

“Cohabiting” women, who live with a partner but might not be married, are more likely to face an unintended pregnancy, too. Surprisingly, Finer and his colleagues found that 81% of the pregnancies among cohabitors were unintended. Teen pregnancies are still mainly unplanned, with around 75% being unintended. But Finer noted that unplanned teen pregnancies are themselves falling, decreasing by about 28% between 2008 and 2011.

Though decreases were observed at all education levels, the size of those decreases was drastically different:

  • Unplanned pregnancies among women without a high school diploma fell by 28%
  • Unplanned pregnancies among high school graduate dropped by 2%
  • Unplanned pregnancies among women who had gone to some college fell by 16%
  • Unplanned pregnancies among college graduates dropped by 14%

In contrast to some reports, primarily from conservative media, an accompanying report from the Guttmacher Institute says that abortion rates in the US are down, not because of state laws that restrict women’s access to reproductive services, or because more women are choosing to carry unplanned pregnancies to term, but because fewer women are getting pregnant in the first place.