Elastographic patterns and Strain ratios of the cervix associated with cervical insufficiency (CI) in pregnant women at 16—24 weeks of gestation have been established. The soft elastographic pattern confirm CI. The intermediate elastographic pattern makes it possible to predict the development of CI within 3±1,64 weeks, which makes it possible to provide timely medical care. The rigid pattern allows to exclude CI and complete further follow-up. Compression elastometry of the cervix in pregnant women using medical silicone as a rigidity standard increases the level of diagnosis of CI up to 100 %. The values of strain coefficients Strain ratio 1 (standard — parametrium) 1,23—1,55 and Strain ratio 2 (standard — medical silicone) 0,26—0,46 are confirmed by CN. Exclude CN values of strain coefficients Strain ratio 1 (standard — parameters) 1,57—1,99 and Strain ratio 2 (standard — medical silicone) 0,48—0,86.