Twins, once a rarity to marvel over, are now a common part of American culture, thanks in large part to increased use of reproductive technology. Twins are conceived naturally just 2 percent of the time; for those who get pregnant with fertility treatments the rate is more than 40 percent.
But as adorable as many of us consider twins, this dramatic rise poses serious health risks, and there are mounting efforts to curb it.
Read the article: http://www.npr.org/2011/03/30/134960899/taming-ivfs-twin-trend

