[Ultrasound of cervix uteri transvaginal in preterm birth]

Premature birth is a social problem due to its implications in the natal mortality and morbidity. This is the reason why it is necessary to establish new methods which could identify pregnant women with high risk of premature birth. Besides the measurable biochemical factors such as fetal fibronectin and salivary estriol, I1-6 sonography is a simple method highly efficient and of reasonable financial costs among all the sonographic means of observing the cervix uteri. The transvaginal sonography is the "golden standard", permitting the most faithful assessment of the pursued parameters--the length of the cervix, the aspect of the internal os (funneling), the cervix index. The experience gathered up to now shows that all of these investigations have a predictive value which is more negative than positive, but when used together they could lead to an improved result.