In a 2007 Pew Research Center telephone survey of 2,000 U.S. men and women, only 41 percent said children are "very important to a successful marriage." In 1990, that figure was 65 percent.
According to the National Institutes of Health, by 2006 one in six U.S. men over age 35 has had a vasectomy, with about half a million getting snipped each year. And while men in their late 30s or 40s are often the ones who opt for the surgery, Dr. Dale McClure, director of Male Infertility at Virginia Mason Medical Center in Seattle, says he sees "a fair number of people under 35" who have undergone the procedure.
"I'm actually seeing more people than I have in the past that are younger that had a vasectomy at age 21 or 22," says McClure.
That doesn't mean doctors are doling out vasectomies like condoms at a free health clinic.
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That's because, Ross says, "there's no 100 percent guarantee in any case that we can reverse it." Within 10 years of having a vasectomy, there's a 90 to 95 percent success rate for reversal surgery. Beyond that, the success rate drops to 75 to 80 percent.
http://www.cnn.com/2008/LIVING/personal/09/08/lw.young.childless.snipped/index.html