Sympathetic neural control of blood pressure across the premenopausal lifespan

The technique of microneurography has advanced our understanding of the sympathetic nervous system's role in the neurovascular control of blood pressure in humans, yet critical knowledge gaps remain, particularly across the premenopausal female lifespan. Historically, premenopausal females have been considered relatively protected from cardiovascular diseases, leading to a disproportionate focus on postmenopausal populations in cardiovascular research. However, emerging evidence contradicts this assumption: premenopausal females with hypertension exhibit 15-20% higher mortality rates than age-matched males, and myocardial infarction deaths are rising fastest among females under the age of 45. This review addresses a major void in the literature by examining sympathetic regulation of blood pressure in premenopausal females and how it is modulated across unique reproductive health states, including menstrual cycling, hormonal contraceptive use, pregnancy, polycystic ovary syndrome, uterine fibroids, and endometriosis. Muscle sympathetic nerve activity fluctuates with some but not all hormonal changes, depending on the population and the conditions under which they are studied. Moreover, corresponding effects on blood pressure vary widely, suggesting a high degree of variability in how sympathetic outflow is transduced into blood pressure in females. Overall, our review highlights the need for longitudinal and mechanistic studies focused on hormonal transitions and specific premenopausal health states to better understand, and eventually mitigate, female-specific cardiovascular risk.