Published: Jan 04, 2012 6:17 PM EST

ATLANTA (AP) - More U.S. women are having twins these days.
    
Health officials say one in every 30 babies is a twin. That's a huge increase over the last 30 years. In 1980, only one in 53 newborns was a twin.
    
Experts attribute the jump mainly to medical treatments and procedures that help infertile couples. But they note that there are more older moms today. For some reason, women in their late 30s have twins at a higher rate.
    
The Centers for Disease Control and Prevention released the twins report on Wednesday.
    
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Online:
    
CDC report: http://www.cdc.gov/nchs/

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