In the last decade, the rate of twin births has declined in the U.S., per CDC data.
The big picture: Early use of IVF contributed to a national twin baby boom. But once fertility treatments got more advanced, doctors increasingly recommended transferring a single embryo to reduce pregnancy risks.
Between the lines: Fraternal twins can result when two embryos are transferred during IVF or when a woman releases two eggs in the same cycle, which becomes more common with age.
By the numbers: The national twin birth rate rose 79% from 1980 to 2014, before dropping an average 1% per year after that, according to the CDC.
Zoom in: The biggest twin birth declines were for mothers age 30 and older. Rates dropped …
- 18% for mothers 30-34.
- 27% for mothers 35-39.
- 46% for mothers 40 and older.
Yes, but: Black mothers already had the highest twin birth rate, and that rate rose 5% nationally over the decade. The CDC didn’t determine what drove the increase.
💭 Carly’s thought bubble: My Class of 2007 high school yearbook devoted an entire page to graduating twins. My fraternal twin sister and I were in it, of course.
