Minireview: Utility of predictive tests for preterm birth used in clinical practice

Abstract

Preterm labor, defined as delivery before 37 weeks of gestation, is a serious obstetric condition that accounts for 11% of pregnancies worldwide. Predictive tests for preterm birth are important, given the personal, economic, and health impact of preterm birth. This review explores the utility of both, the current predictive tests used in clinical practice (maternal characteristics, cervical length and biochemical markers), as well as the new emerging tests. An electronic search was carried out in the scientific health databases: PUBMED, COCHRANE, SCIELO, national universities virtual repositories were also reviewed, using the following search items and their combinations: preterm delivery, cervical length, cervical shortening, cervicometry, fetal fibronectin, risk factors, and maternal characteristics. We included papers in English and Spanish published from 2006 to 2020, which responded to the aim of the review: the utility of predictive test for preterm delivery. A total of 30 articles were included in this review. There are multiple scientific criteria on the different current techniques to identify patients at risk and achieve adequate prevention of preterm birth. Measurement of cervical length by transvaginal ultrasound is the most cost-effective method in women with a history of preterm labor or symptoms of preterm labor; the current evidence allows us to affirm that it is also essential to perform routine cervicometry in all patients, even with low risk. There are promising ultrasound predictive methods such as cervical elastography and cervical consistency index, but there are limitations in their technical implementation, it is proposed that they could be a possible alternative in the future, that can be combined with cervical length measurement. Also, adding cervical length easurement to biochemical tests appears to improve predictive accuracy.