Twin birth rate at lowest level in decade, and that’s a good thing, doctors say

NEW YORK — Fewer U.S. families are seeing double, according to a government report that finds a drop in new twins.

Twin births steadily increased for more than three decades, driven largely by older white moms undergoing fertility treatments.

But the rate of twin births apparently peaked in 2014 and has fallen 4 percent since. Last year, the rate hit its lowest point in a decade, the Centers for Disease Control and Prevention reported Thursday.

The drop is modest, but health officials say it is good news. Pregnancy with more than one raises the risks of complications and death for both the mother and her fetuses. Complications include premature birth and a low birth weight.

“In the media, there are often stories about very cute twins and talking about how great to have two babies at the same time,” said the CDC’s Dr. Dmitry Kissin. But “these stories don’t focus on the risk.”

Last year, about 124,000 babies were twins — about 1 of every 31 births, the same as a decade earlier. The rate peaked at 1 in 29 in 2014.

The CDC did not release figures on triplets or other multiple births, but said data suggests it’s trending the same way.

Why the decline? Experts can’t say for sure. But Joyce Martin, the report’s lead author, noted the decrease occurred only in white women and in women 30 or older. Those women are the biggest customers of expensive in vitro fertilization treatments, which are involved in roughly 15 percent of multiple births. And there’s been a shift in how that technique is done.