The number of twins being born in the U.S. is at an all-time high, but not so much for other multiples. Correspondent Scott Carr report increase in twin births may have increased, but birth rates of other multiples are at their lowest in two decades. Of the nearly four million babies born last year, more than 135,000 were twins. That’s about 1 in every 29 babies. In 1980, only 1 in every 53 babies was a twin. Why the twin increase? More women are waiting until they are older to have babies, and mothers in their 30s are more likely to have twins than younger women. On the other hand, doctors have been implanting fewer embryos during in vitro fertilization than in the past, in recognition that more embryos increase the risk of dangerous complications. Experts say the rate of triplet and higher-order births has fallen 40% from its 1998 peak.
