Fertility drugs increasing birth of multiples

(CNN) - Scientists say fertility drugs alone may be behind the drastic rise in multiple births in the U.S.

This is significant because for a long time it was believed the culprit was in-vitro fertilization.

The New England Journal of Medicine found that by 2011, 36 percent of twin births and 77 percent of triplet births were the result of fertility treatments including drugs.

Researchers say this is a public health issue because despite medical advancements, multiple births are still risky for both mother and babies.

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