Factors associated with fetal vulnerability and to fetal death

Abstract

Fetal growth restriction estimated by its SGA (Small for Gestational Age - SGA) proxy, as already mentioned in the presentation of the thematic project, is part of the causal chain of fetal deaths. Recent studies have shown that biological vulnerability is expressed by the concomitant presence of prematurity, low birth weight, and altered fetal growth, either fetal growth restriction (birth weight below the 10th percentile of weight for gestational age) or fetal growth. Fetal enlargement (estimated by its proxy GIG - Giants for Gestational Age) plays an important role in early neonatal mortality in Brazil. Another study on fetal deaths in the city of São Paulo found that abnormal fetal growth was present in 40% of fetal deaths. It was also found that the concomitant presence of fetal growth restriction, low birth weight, and prematurity was present in 27.7% of fetal deaths. These fetuses had a risk of death of 149.64 (CI: 131.62; 170.13) times that of those born at term, not low birth weight, and Adequate for Gestational Age - AGA. There was also an increased risk of death when the fetuses were preterm, LGA, and low birth weight (RR=258.89; CI:203.17;329.89).However, the aforementioned studies were carried out with data from the mortality information systems (SIM) and live births (SINASC), which include a few variables associated with fetal growth. the subproject now proposed will enable a better assessment of risk factors associated with fetal biological vulnerability, as it will have information on maternal reproductive history, presence of maternal and other conditions, as well as information on prenatal care, the placenta, angiogenic factors, of autopsies and atmospheric pollution, collected in this thematic project.