In California, from 2004 to 2015, the percent of women of reproductive age (ages 15 to 44) with gestational diabetes increased from 5.3 percent to 9.5 percent. The maps below show the percent of women with gestational diabetes at three different time periods: 2004-2006, 2009-2011 and 2013-2015. In 2004-2006, no counties had rates above nine percent. In 2009-2011, ten counties had rates above nine percent. By 2013-2015, more than half the counties had rates above nine percent.