The effect of Ambiant heat exposure early in pregnancy on the frequency of congenital heart defects: Systematic Review Protocol
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Abstract
Introduction: Fetal development is highly sensitive to temperature extremes during pregnancy, partly due to the reduced thermoregulatory capacity of pregnant women. This vulnerability has been linked to an increased risk of congenital heart disease (CHD). With global warming expected to increase extreme heat events, understanding the relationship between maternal heat exposure and CHD risk has become increasingly urgent.
Objective: This systematic review aims to evaluate existing evidence on the impact of maternal high-temperature exposure on the incidence of CHD.
Methods: We will follow the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Searches will be conducted in PubMed, Embase, Scopus, and Google Scholar databases using tested and validated search algorithms. We will include any type of study, published in English or French, involving pregnant women and/or neonates that directly evaluates the relationship between high-temperature exposure during pregnancy and CHD. Experimental or modelling studies involving animals and those examining the association between maternal fever and CHD will be excluded. Study selection, data extraction, and risk of bias assessment will be conducted by two independent reviewers. The quality and risk of bias will be assessed using the Newcastle-Ottawa Scale. The main outcomes are the incidence and types of CHD diagnosed in infant.
PROSPERO registration number : CRD42024584967
Keywords:
Hot Temperature, Extreme Heat, Pregnancy, Maternal Exposure, Congenital Abnormalities, Heart Defects Congenital, Infant, Newborn##plugins.themes.academic_pro.article.details##

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