"More women are going kid-free by choice, thanks to more accessible and better contraception and a decrease in social stigma related to non-motherhood." Salon looks at motherhood data. "To birth or not to birth? According to a new study of American women, the answer is increasingly 'not.' Researchers at the Pew Research Center find that 18 percent of women now end their childbearing years without biological children, compared to 10 percent in 1976...Some women who end up childless, of course, aren't in that position by decision. Delaying marriage, pursuing advanced degrees and putting off having children while developing a career often result in fertility problems when women try to get pregnant later in their childbearing years."