Ultrasonographic examination of the uterine cervix is better than cervical digital examination as a predictor of the likelihood of premature delivery in patients with preterm labor and intact membranes. - Gomez,R.; Galasso,M.; Romero,R.; Mazor,M.; Sorokin,Y.; Goncales,L.; Treadwell,M. (Am J Obstet Gynecol, 1994)