Nope, you don’t need an eye exam — you really are seeing double. According to a recent CDC report, the birth rate for twins has increased a whopping 76 per cent since 1980.
In fact, one in every 30 babies born in 2009 was a twin (compared to 1980, when the rate was one baby in every 53). What’s with the binary-baby boom? One factor contributing to the upsurge: The age of mothers has trended up over the years, and a woman in her thirties is more likely to have twins than someone in her twenties, according to the study’s lead author, epidemiologist Joyce Martin, MPH. However, while age is an independent risk factor for twins, it also tends to correlate with increased use of fertility treatments, which was likely the biggest contributor to the spike in twin births.