Imaging Considerations in Pregnancy

摘要： Pregnancy is a complex interplay of multiple physiologic states maintaining balance between the needs of mother and fetus. This is reflected in hormonal, hemodynamic, hematologic, and immunologic changes at both global and cellular levels. A decrease in brain size and increase in heart, pituitary, thyroid, and kidney sizes secondary to hormonal influences have been observed during pregnancy.1,2 Circulating hormones also have trophic effect on preexisting neoplasms, such as meningioma, pituitary adenomas, and breast carcinoma.3 The increased blood volume and clotting factor alterations increase the risk of stroke, especially during the peripartum and postpartum period.4,5 Hemodynamic and hormonal effects on vessel wall integrity can lead to worsening of aneurysm with possible hemorrhage, whereas prolonged labor may increase risk of infarct from venous thrombosis or dissection.6,7 In contrast, increased cortisol levels have shown to improve autoimmune diseases such as multiple sclerosis by exerting inhibitory effect on T-cell function8–10