Epidemiology and pathophysiology of primary versus secondary intracranial hemorrhage in pregnant and nonpregnant patients: A literature review.

Intracranial hemorrhage (ICH) is a critical condition with a high risk of mortality and morbidity. Understanding the incidence and pathophysiology of ICH in both pregnant and non-pregnant patients could improve early detection and lead to more optimal management. In this narrative review, we aim to compare the epidemiology, risk factors, and pathophysiology of primary and secondary ICH in these two groups of patients. Hypertensive vasculopathy and cerebral amyloid angiopathy (CAA) are the two most common pathophysiologies of primary ICH. In addition, ICH in pregnancy was related to hypertensive disorders of pregnancy, including pre-eclampsia, eclampsia, and HELLP (Hemolysis, Elevated Liver enzymes, and Low Platelets) syndrome. The incidence of ICH was mostly reported to be similar in pregnancy and postpartum (PP), but some studies reported a higher incidence in the PP period. The risk of primary ICH in pregnant patients was reported to be over four times higher than in non-pregnant patients. Secondly, ICH is caused by identifiable factors such as rupture of arterio-vascular malformations (AVM) and aneurysms, stimulant drug use, vasculitis, neoplasm, moyamoya disease, cerebral venous sinus thrombosis or cavernous malformations, and coagulopathies. AVMs are seen to be much more common as a cause of ICH in pregnant/PP patients compared to the general population. Other identifiable risk factors for pregnancy/PP-related ICH are Black or Asian race and older maternal age. The review emphasizes the importance of early identification, risk factor management, and appropriate interventions to improve clinical outcomes in pregnant and postpartum women experiencing ICH.