Fear. Convenience. Emergency. All are among the reasons why some celeb moms' babies are born via C-section. And it's not just Hollywood moms: The rate of caesarean sections are rising worldwide -- surpassing recommendations by the World Health Organization that C-sections make up less than 15% of all births. In the U.S., about 1 in 4 babies was born by C-section in 2004, according to the CDC.