1. 1 World Health Organization (WHO). Born too soon: the global action report on preterm birth. 2012 [cited 2021 Apr 16]. Available from: https://www.who.int/publications/i/item/9789241503433
2. Prediction of patient-specific risk of early preterm delivery using maternal history and sonographic measurement of cervical length: a population-based prospective study;To;Prediction of patient-specific risk of early preterm delivery using maternal history and sonographic measurement of cervical length: a population-based prospective study,2006
3. Mid-trimester endovaginal sonography in women at high risk for spontaneous preterm birth;Owen;JAMA,2001
4. Vaginal progesterone for preventing preterm birth and adverse perinatal outcomes in singleton gestations with a short cervix: a meta-analysis of individual patient data;Romero;Am J Obstet Gynecol,2018
5. 5 Instituto Brasileiro de Geografia e Estatística (IBGE). Rio Grande do Sul: População. 2021 [citado 2023 May 6]. Disponível em https://cidades.ibge.gov.br/brasil/rs/panorama