Department of Obstetrics and Gynecology, School of Medical Sciences, University of Campinas, Brazil.
BMC Pregnancy Childbirth. 2010 May 19;10:22. doi: 10.1186/1471-2393-10-22.
The occurrence of preterm birth remains a complex public health condition. It is considered the main cause of neonatal morbidity and mortality, resulting in a high likelihood of sequelae in surviving children. With variable incidence in several countries, it has grown markedly in the last decades. In Brazil, however, there are still difficulties to estimate its real occurrence. Therefore, it is essential to establish the prevalence and causes of this condition in order to propose prevention actions. This study intend to collect information from hospitals nationwide on the prevalence of preterm births, their associated socioeconomic and environmental factors, diagnostic and treatment methods resulting from causes such as spontaneous preterm labor, prelabor rupture of membranes, and therapeutic preterm birth, as well as neonatal results.
METHODS/DESIGN: This proposal is a multicenter cross-sectional study plus a nested case-control study, to be implemented in 27 reference obstetric centers in several regions of Brazil (North: 1; Northeast: 10; Central-west: 1; Southeast: 13; South: 2). For the cross sectional component, the participating centers should perform, during a period of six months, a prospective surveillance of all patients hospitalized to give birth, in order to identify preterm birth cases and their main causes. In the first three months of the study, an analysis of the factors associated with preterm birth will also be carried out, comparing women who have preterm birth with those who deliver at term. For the prevalence study, 37,000 births will be evaluated (at term and preterm), corresponding to approximately half the deliveries of all participating centers in 12 months. For the case-control study component, the estimated sample size is 1,055 women in each group (cases and controls). The total number of preterm births estimated to be followed in both components of the study is around 3,600. Data will be collected through a questionnaire all patients will answer after delivery. The data will then be encoded in an electronic form and sent online by internet to a central database. The data analysis will be carried out by subgroups according to gestational age at preterm birth, its probable causes, therapeutic management, and neonatal outcomes. Then, the respective rates, ratios and relative risks will be estimated for the possible predictors.
These findings will provide information on preterm births in Brazil and their main social and biological risk factors, supporting health policies and the implementation of clinical trials on preterm birth prevention and treatment strategies, a condition with many physical and emotional consequences to children and their families.
早产的发生仍然是一个复杂的公共卫生问题。它被认为是新生儿发病率和死亡率的主要原因，导致幸存儿童发生后遗症的可能性很高。在一些国家，早产的发病率各不相同，但在过去几十年中，它明显增加了。然而，在巴西，仍然难以估计其实际发生情况。因此，确定这种情况的流行率和原因对于提出预防措施至关重要。本研究旨在收集全国医院关于早产的流行率、与其相关的社会经济和环境因素、自发性早产、胎膜早破和治疗性早产等原因导致的诊断和治疗方法以及新生儿结果的信息。
方法/设计：本研究是一项多中心的横断面研究加嵌套病例对照研究，将在巴西几个地区的 27 个参考产科中心实施（北部：1；东北部：10；中西部：1；东南部：13；南部：2）。在横断面部分，参与中心应在六个月的时间内对所有住院分娩的患者进行前瞻性监测，以确定早产病例及其主要原因。在研究的头三个月，还将对与早产相关的因素进行分析，将早产的妇女与足月分娩的妇女进行比较。对于流行率研究，将评估 37000 例分娩（足月和早产），约占所有参与中心在 12 个月内分娩的一半。对于病例对照研究部分，估计每组（病例和对照）的样本量为 1055 名妇女。在研究的两个部分中，估计将跟踪大约 3600 例早产。通过问卷收集所有患者在分娩后回答的信息。然后，将数据编码为电子表格形式，并通过互联网在线发送到中央数据库。数据分析将根据早产时的胎龄、其可能的原因、治疗管理和新生儿结局进行亚组分析。然后，将估计可能的预测因素的各自率、比值和相对风险。
这些发现将提供有关巴西早产及其主要社会和生物学危险因素的信息，为卫生政策提供支持，并为预防和治疗早产的临床试验提供支持，这是一种对儿童及其家庭有许多身体和情感后果的情况。
