Nov. 27 (UPI) -- Birth rates in the United States continued to decline in 2018, particularly for younger mothers, an analysis by the Centers for Disease Control and Prevention has revealed.

In its latest National Vital Statistics Report, released Wednesday, the agency reported that fewer than 4 million births were registered across the country in 2018, a 2 percent decline over the prior year. Overall, according to CDC figures, the American birth rate has been in decline since the early 2000s.


Among women between 15 and 44 years of age, the general fertility rate also declined by 2 percent from 2017 to 2018, from 60.3 to 59.1 births per 1,000 population. Notably, the birth rate among women between 15 and 19 years of age declined by 7 percent from year to year, while dropping by 4 percent for those between 20 and 24 years of age and by 3 percent for those between 25 and 29.

The birth rate also fell by 1 percent for women between 30 and 34 years of age in 2018, but increased by the same amount for women between 35 and 29. The figure increased by 2 percent for women between 40 and 44 years of age, and remained unchanged from year to year for women 45 years of age and older.

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In all, the CDC reported, the total fertility rate in the U.S. declined by 2 percent from 2017 to 2018, from 1,765.5 to 1,729.5 births per 1,000 women. And, birth rates for both married and unmarried women declined by 2 percent from 2017 to 2018 -- with 85.6 and and 40.1 births per 1,000 women, respectively.

Twin and triplet higher-order multiple birth rates also declined in 2018, by 2 percent and 8 percent, respectively. The CDC reported that the number of triplet and multiple births in 2018, 3,525, was the lowest number reported since 1991 and less than one-half of the highest number ever reported, which was 7,663 in 2003.

The percentage of women who began prenatal care in the first trimester of pregnancy rose to 77.5 percent in 2018 from 77.3 percent the previous year. The percentage of all women who smoked during pregnancy declined to 6.5 percent, a 6 percent decline from 2017. The cesarean delivery rate decreased to 31.9 percent in 2018 following an increase to 32 percent in 2017. That figure peaked at 32.9 percent in 2009.

Medicaid was the source of payment for 42.3 percent of all 2018 births, down 2 percent from 2017. The preterm birth rate rose for the fourth straight year to just over 10 percent in 2018, while the rate of low-birth-weight babies delivered remained unchanged at approximately 8.3 percent.