“…Living in high and very high‐altitude regions has been associated with a higher prevalence of craniosynostosis, congenital heart defects, microtia, cleft lip, preauricular tag, branchial arch anomaly, constriction band, and imperforate anus (Alderman et al, 1995; Alzamora et al, 1953; Castilla et al, 1999; Lopez‐Camelo & Orioli, 1996; Miao et al, 1988; Orioli et al, 2003; Poletta et al, 2007). Nevertheless, against the hypothesis that hypoxic environments as a risk factor, some other congenital malformations such as anencephaly, encephalocele, spina bifida, hydrocephaly, pes equinovarus, and hypospadias had a lower prevalence at high altitudes than low altitude locations, being low altitudes a risk factor for these malformations (Castilla et al, 1999; Fernández et al, 2016; Saldarriaga et al, 2007).…”