Passini R Jr, Cecatti JG, Lajos GJ, Tedesco RP, Nomura ML, Dias TZ, Haddad SM, Rehder PM, Pacagnella RC, Costa ML, Sousa MH; Brazilian Multicentre Study on Preterm Birth study group. Brazilian multicentre study on preterm birth (EMIP): prevalence and factors associated with spontaneous preterm birth. PLoS One. 2014 Oct 9;9(10):e109069. doi: 10.1371/journal.pone.0109069. Erratum in: PLoS One. 2015;10(2):e0116843. PMID: 25299699; PMCID: PMC4192080.
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 among women with at least one previous birth: a previous preterm birth (ORadj = 3.19, 2.30–4.43), multiple pregnancy (ORadj = 29.06, 8.43–100.2), cervical insufficiency (ORadj = 2.93, 1.07–8.05), foetal malformation (ORadj = 2.63, 1.43–4.85), polyhydramnios (ORadj = 2.30, 1.17–4.54), vaginal bleeding (ORadj = 2.16, 1.50–3.11), and previous abortion (ORadj = 1.39, 1.08–1.78). High BMI (ORadj = 0.94, 0.91–0.97) and weight gain during gestation (ORadj = 0.92, 0.89–0.95) 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.
Disponível Em: <https://www.ncbi.nlm.nih.gov/>