The number of American women without children has risen to an all-time high of 1 in 5, a jump since the 1970s when 1 in 10 women ended their childbearing years without having a baby, according to the Pew Research Center. About 1.9 million women aged 40-44 - or 18 percent - were childless in 2008, an 80 percent increase since 1976, when just 580,000 -- 10 percent of those in that age bracket -- had never given birth, the Census Bureau s Current Population Survey shows.