Barbara Fuenzalida

Keywords Placental adaptations Iron transfer Prenatal stress Sex differences Evidence before this study A comprehensive literature search was conducted using PubMed, Google, and Web of Science. Search terms included: iron, iron transfer, iron deficiency, placenta, stress, prenatal stress, environmental stress, and psychological stress. The search covered publications from the past 35 years up to May 2025.

Introduction Approximately 80–90% of pregnant women use at least one medicinal drug, either to treat pre-existing maternal/fetal conditions or to manage complications arising during pregnancy (Mitchell et al., 2011). Although the use of medications in pregnancy is an essential aspect of obstetrical care, it remains a major concern due to potential risks to fetal and placental development. While some drugs are essential, their potentially harmful effects remain poorly understood.