The average age at which women in the U.S. give birth to their first baby has declined for the first time in nearly 40 years, reports the Wall Street Journal. According to the National Center for Health Statistics, mothers’ mean age at their first childbirth fell to 25.0 years in 2006, from 25.2 in 2005. Women aged 20 to 24 led the shift, with a 5% increase in the rate of first births. Whether this one-year reversal signals a trend remains to be seen, but experts speculating it might signal a shift in attitude among young women who assume they’ll have career and family. But it also could be influenced by the rising numbers of Hispanics, who tend to start families earlier and a 4 per cent rise in the rate of first births to teenagers aged 15 to 19.