Teen birth rates fell to record lows over the past decade, with the largest declines among minority teens, according to data from the CDC's National Vital Statistics System.

Overall birth rates for teens ages 15-19 dropped 61% from 1991 to 2014, with a 41% drop from 2006 to 2014 (from 41.4 to 24.2 per 1,000 births), reported Lisa Romero, DrPH, of the CDC, and colleagues.

Writing in the Morbidity and Mortality Weekly Report, they reported that from 2006-2014, the birth rate among Hispanic teens was cut in half, with the rate among non-Hispanic black teens down 44%, thereby reducing the disparity between minority and white teen births.

However, the disparity didn't disappear altogether, in part because teen births among whites declined 35% in the same time period.

"The United States has made remarkable progress in reducing both teen pregnancy and racial and ethnic differences, but the reality is, too many American teens are still having babies," said CDC Director Tom Frieden, MD, in a statement. "By better understanding the many factors that contribute to teen pregnancy we can better design, implement, evaluate, and improve prevention interventions and further reduce disparities."



Romero and colleagues cited "geographic and socioeconomic disparities" as a potential reason for the gap between birth rates. To explore this possibility, they analyzed data from the Census' American Community Survey and, not surprisingly, found that unemployment rates, parental education and family income all were associated with variations in birth rates.

Counties in the highest quintiles for teen birth rates had a higher mean percentage of unemployment for persons ages ≥16 years (10.5%), a lower percentage of the population ages ≥25 years with an associate's degree or higher (19.9%) and a lower mean family income ($46,005) compared with counties in the lowest quintiles for teen birth rates (7.6%, 40.4% and $73,967, respectively; P<0.001 for all comparisons).

The authors note these social determinants linked to teenage births seem to be more common in communities with higher proportions of racial ethnic minorities, and conclude that ongoing efforts are required to integrate social determinants of health into teen pregnancy prevention.

"These data underscore that the solution to our nation's teen pregnancy problem is not going to be a one-size-fits-all," said Romero in a statement. "We can ensure the success of teen pregnancy prevention efforts by capitalizing on the expertise of our state and local public health colleagues. Together, we can work to implement proven prevention programs that take into account unique, local needs."

Triplet and Higher-Order Birth Rate Falls
Another CDC report, issued as an NCHS Data Brief, indicated that the rate of triplet and higher-order multiple births among U.S. women was nearly halved from 1998 to 2014, with notable declines among older women and those of Hispanic origin.

The overall rate was down 41%, from 193.5 to 113.5 per 100,000 births, with a decline of nearly 50% or more among women older than age 25, reported Joyce A. Martin, MPH, and colleagues in the National Center for Health Statistics.

In fact, the largest declines were among older mothers (ages ≥45 years), with triplet and higher-order birth rates down by two-thirds in that time frame (2,326.0 to 769.9 per 100,000 births). Mothers who were ≥45 years of age were also more than 35 times likely to give birth to triplets than teen mothers.

Demographically, non-Hispanic white women exhibited the largest declines (down 46% from 1998 to 2014) in these types of births. Non-Hispanic white women were also 57% more likely to give birth to triplets or have higher-order births than non-Hispanic black women.

This reverses the trend from the 1980s and 1990s, when increasingly older mothers, as well as increased use of fertility treatments, propelled a four-fold increase in the triplet and higher-order birth rate. Martin and colleagues cited changes in assisted reproductive technologies (ART), such as reducing the number of transferred embryos, as one potential reason for the decline.

Despite the progress at reducing the rate of triplets and higher-order births, the researchers noted that current rates remain three times greater than before ART and non-ART therapies, such as ovulation-inducing drugs, became broadly available.