Pregnant women with more seizures have lower allopregnanolone concentrations

Insights into neurosteroids and their role in women with epilepsy

Epilepsy, is a serious neurological condition, characterized by recurring, unprovoked seizures and affects over 50 million people worldwide. Epilepsy has an equal prevalence in males and females, and occurs throughout the life span. Women with epilepsy (WWE) present with unique challenges due to the cyclical fluctuation of sex steroid hormone concentrations during their life course. These shifts in sex steroid hormones and their metabolites are intricately intertwined with seizure susceptibility and affect epilepsy during the life course of women in a complex manner. Here we present a review encompassing neurosteroids-steroids that act on the brain regardless of their site of synthesis in the body; the role of neurosteroids in women with epilepsy through their life-course; exogenous neurosteroid trials; and future research directions. The focus of this review is on progesterone and its derived neurosteroids, given the extensive basic research that supports their role in modulating neuronal excitability.

Female sex steroids and epilepsy: Part 1. A review of reciprocal changes in reproductive systems, cycles, and seizures

Seizures, antiseizure medications, and the reproductive systems are reciprocally entwined. In Section 2 of this review, we outline how seizures may affect the hypothalamic-pituitary-gonadal axis, thereby altering sex steroids, and changes in sex steroids across the menstrual cycle and changes in pharmacokinetics during pregnancy may alter seizure susceptibility. The literature indicates that females with epilepsy experience increased rates of menstrual disturbances and reproductive endocrine disorders. The latter include polycystic ovary syndrome, especially for females on valproate. Studies of fertility have yielded mixed results. We aim to summarize and attempt to detangle the existing knowledge on these reciprocal interactions. The menstrual cycle causes changes in seizure intensity and frequency for many females. When this occurs perimenstrually, during ovulation, or in association with an inadequate luteal phase, it is termed catamenial epilepsy. There is a clear biophysiological rationale for how the key female reproductive neurosteroids interact with the brain to alter the seizure threshold, and Section 3 outlines this important relationship. Critically, what remains unknown is the specific pathophysiology of catamenial epilepsy that describes why not all females are affected. There is a need for mechanism-focused investigations in humans to uncover the complexity of the relationship between reproductive hormones, menstrual cycles, and the brain.

Mechanisms linking neurological disorders with reproductive endocrine dysfunction: Insights from epilepsy research

Gonadal hormone actions in the brain can both worsen and alleviate symptoms of neurological disorders. Although neurological conditions and reproductive endocrine function are seemingly disparate, compelling evidence indicates that reciprocal interactions exist between certain disorders and hypothalamic-pituitary-gonadal (HPG) axis irregularities. Epilepsy is a neurological disorder that shows significant reproductive endocrine dysfunction (RED) in clinical populations. Seizures, particularly those arising from temporal lobe structures, can drive HPG axis alterations, and hormones produced in the HPG axis can reciprocally modulate seizure activity. Despite this relationship, mechanistic links between seizures and RED, and vice versa, are still largely unknown. Here, we review clinical evidence alongside recent investigations in preclinical animal models into the contributions of seizures to HPG axis malfunction, describe the effects of HPG axis hormonal feedback on seizure activity, and discuss how epilepsy research can offer insight into mechanisms linking neurological disorders to HPG axis dysfunction, an understudied area of neuroendocrinology.

Status epilepticus in pregnancy

Status epilepticus is a frequent neurological emergency associated with a case fatality of about 10-15% depending on age, cause, and other factors, and a high burden for patients, caregivers, and society. In pregnancy, it can occur in two different clinical constellations: (1) In women with a history of epilepsy and (2) as new onset status epilepticus in pregnancy (NOSEP). Both entities are relatively rare but differ in terms of etiology. Here we describe the epidemiology, etiologies, diagnosis, clinical course with the maternal and fetal outcome, and the suggested management strategies for either manifestation. This paper was presented at the 8th London-Innsbruck Colloquium on Status Epilepticus and Acute Seizures held in September 2022.