The Molecular and Cellular Basis of Physiological Changes in Pregnancy and Its Implications in Neurologic and Ophthalmic Pathologies

Pregnancy orchestrates profound neurological, hormonal, and anatomical transformations in the maternal brain, preparing it for caregiving and infant bonding. Neuroimaging reveals structural changes such as gray matter reductions and white matter reorganization during pregnancy, followed by partial recovery postpartum. These adaptations are modulated by fluctuating levels of estradiol, progesterone, prolactin, and oxytocin, which coordinate neuroplasticity and behavioral readiness. At the molecular and cellular levels, pregnancy hormones drive synaptic remodeling, neurogenesis, and glial activity. Together, these changes support maternal motivation, attachment, and responsiveness, highlighting the maternal brain's dynamic plasticity across gestation and the postpartum period. Also, pregnancy induces profound physiological changes, particularly in vascular, hormonal, and neurologic systems, to support maternal and fetal health. While these adaptations are essential, they can predispose pregnant individuals to various neurologic and ophthalmic pathologies. This review explores how pregnancy-related changes-including hypercoagulability, pituitary enlargement, hormonal fluctuations, and immunological modulation-contribute to conditions such as stroke, idiopathic intracranial hypertension, preeclampsia-associated visual disturbances, and demyelinating disorders like neuromyelitis optica spectrum disorder and multiple sclerosis. Additionally, ocular manifestations of systemic diseases like diabetic retinopathy and thyroid orbitopathy are discussed. Understanding these complex interactions is critical for prompt recognition, accurate diagnosis, and appropriate management of vision-threatening and neurologically significant complications during pregnancy. Nevertheless, many aspects of physiological and pathological changes during and after pregnancy remain unknown and warrant further investigation.