Brazilian Multicentre Study on Preterm Birth (EMIP): prevalence and factors associated with spontaneous preterm birth

• Grant number: 14/18918-7
• Support Opportunities: Regular Research Grants - Publications - Scientific article
• Start date: November 01, 2014
• End date: April 30, 2015
• Field of knowledge: Health Sciences - Medicine - Maternal and Child Health
• Principal Investigator: Renato Passini Júnior
• Grantee: Renato Passini Júnior
• Host Institution: Faculdade de Ciências Médicas (FCM). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil
• City of the host institution: Campinas

Abstract

Background: Preterm birth rate is increasing and is currently a worldwide concern. The purpose of this study was to estimate the prevalence of preterm birth in a sample of health facilities in Brazil and to identify the main risk factors associated with spontaneous preterm births. Methods and Findings: This was a multicentre cross sectional study on preterm births in 20 referral obstetric hospitals with a case-control component to identify factors associated with spontaneous preterm birth. Surveillance was implemented at all centres to identify preterm births. For eligible consenting women, data were collected through a post-delivery questionnaire completed with information from all mother-newborn medical records until death or discharge or at a maximum of 60 days post-delivery, whichever came first. The risk of spontaneous preterm birth was estimated with OR and 95%CI for several predictors. A non-conditional logistic regression analysis was then performed to identify independently associated factors. The overall prevalence of preterm birth was 12.3%. Among them, 64.6% were spontaneous and 35.4% therapeutic. In the case-control component, 2,682 spontaneous preterm births were compared to a sample of 1,146 term births. Multivariate analyses identified the following as risk factors for spontaneous preterm birth: a previous preterm birth, multiple pregnancy, cervical insufficiency, foetal malformation, polyhydramnios, vaginal bleeding, an inadequate number of prenatal care visits, previous abortion, and urinary tract infection. Obesity and weight gain during gestation were found to be protective factors. Conclusions: The preterm birth rate in these health facilities in Brazil is high and spontaneous preterm births account for two thirds of them. A better understanding of the factors associated with spontaneous preterm birth is of utmost importance for planning effective measures to reduce the burden of its increasing rates. (AU)