CDC NCHS released a new data brief this morning on twin births in the United States from 1980 to 2009. Here are the key findings from the report:
• In 2009, 1 in every 30 babies born in the United States was a twin, compared with 1 in every 53 babies in 1980.
• The twin birth rate rose 76 percent from 1980 through 2009, from 18.9 to 33.3 per 1,000 births.
• If the rate of twin births had not changed since 1980, approximately 865,000 fewer twins would have been born in the United States over the last three decades.
• Twinning rates rose by at least 50 percent in the vast majority of states and the District of Columbia.
• Over the three decades, twin birth rates rose by nearly 100 percent among women aged 35–39 and more than 200 percent among women aged 40 and over.
• The older age of women at childbirth in 2009 compared with three decades earlier accounts for only about one-third of the rise in twinning over the 30 years.
Chart appears in the NCHS Data Brief “Three Decades of Twin Births in the United States, 1980–2009”, January 2012. [NCHS Pressroom]