ATLANTA — The number of twins born in the U.S. soared over the past three decades, mostly the result of test-tube babies and women waiting to have children until their 30s, when the chances of twins increase.
In 2009, 1 in every 30 babies born in the U.S. was a twin, an astounding increase over the 1-in-53 rate in 1980, according to a government report issued Wednesday.
“When people say it seems like you see more twins nowadays, they’re right,” said Joyce Martin, an epidemiologist who co-authored the Centers for Disease Control and Prevention report.
For some unknown reason, mothers in their 30s are more likely to have twins than younger or older women. As much as a third of the increase can be attributed to that, Martin said.
The rest of the rise is due to fertility drugs and treatments.
“You have a double whammy going on. There are more older moms and more widespread use of fertility-enhancing therapies,” Martin said.
