Massey Documents by Type

Permanent URI for this communityhttps://mro.massey.ac.nz/handle/10179/294

Browse

Has files: YesSubject: search.filters.subject.menstrual cycle

Search Results

Now showing 1 - 3 of 3
  • Thumbnail Image
    Item
    A contemporary understanding of iron metabolism in active premenopausal females
    (Frontiers Media S.A, 2022) Badenhorst CE; Forsyth AK; Govus AD
    Iron metabolism research in the past decade has identified menstrual blood loss as a key contributor to the prevalence of iron deficiency in premenopausal females. The reproductive hormones estrogen and progesterone influence iron regulation and contribute to variations in iron parameters throughout the menstrual cycle. Despite the high prevalence of iron deficiency in premenopausal females, scant research has investigated female-specific causes and treatments for iron deficiency. In this review, we provide a comprehensive discussion of factors that influence iron status in active premenopausal females, with a focus on the menstrual cycle. We also outline several practical guidelines for monitoring, diagnosing, and treating iron deficiency in premenopausal females. Finally, we highlight several areas for further research to enhance the understanding of iron metabolism in this at-risk population.
  • Thumbnail Image
    Item
    Cerebral autoregulation across the menstrual cycle in eumenorrheic women
    (Wiley Periodicals LLC on behalf of The Physiological Society and the American Physiological Society, 2022-05-06) Korad S; Mündel T; Fan J-L; Perry BG
    There is emerging evidence that ovarian hormones play a significant role in the lower stroke incidence observed in pre-menopausal women compared with men. However, the role of ovarian hormones in cerebrovascular regulation remains to be elucidated. We examined the blood pressure-cerebral blood flow relationship (cerebral autoregulation) across the menstrual cycle in eumenorrheic women (n = 12; mean ± SD: age, 31 ± 7 years). Participants completed sit-to-stand and Valsalva maneuvers (VM, mouth pressure of 40 mmHg for 15 s) during the early follicular (EF), late follicular (LF), and mid-luteal (ML) menstrual cycle phases, confirmed by serum measurement of progesterone and 17β-estradiol. Middle cerebral artery blood velocity (MCAv), arterial blood pressure and partial pressure of end-tidal carbon dioxide were measured. Cerebral autoregulation was assessed by transfer function analysis during spontaneous blood pressure oscillations, rate of regulation (RoR) during sit-to-stand maneuvers, and Tieck's autoregulatory index during VM phases II and IV (AI-II and AI-IV, respectively). Resting mean MCAv (MCAvmean ), blood pressure, and cerebral autoregulation were unchanged across the menstrual cycle (all p > 0.12). RoR tended to be different (EF, 0.25 ± 0.06; LF; 0.19 ± 0.04; ML, 0.18 ± 0.12 sec-1 ; p = 0.07) and demonstrated a negative relationship with 17β-estradiol (R2  = 0.26, p = 0.02). No changes in AI-II (EF, 1.95 ± 1.20; LF, 1.67 ± 0.77 and ML, 1.20 ± 0.55) or AI-IV (EF, 1.35 ± 0.21; LF, 1.27 ± 0.26 and ML, 1.20 ± 0.2) were observed (p = 0.25 and 0.37, respectively). Although, a significant interaction effect (p = 0.02) was observed for the VM MCAvmean response. These data indicate that the menstrual cycle has limited impact on cerebrovascular autoregulation, but individual differences should be considered.
  • Thumbnail Image
    Item
    Pain Across the Menstrual Cycle: Considerations of Hydration
    (Frontiers Media S.A., 8/10/2020) Tan B; Philipp M; Hill S; Che Muhamed AM; Mündel T
    Chronic pain - pain that persists for more than 3 months - is a global health problem and is associated with tremendous social and economic cost. Yet, current pain treatments are often ineffective, as pain is complex and influenced by numerous factors. Hypohydration was recently shown to increase ratings of pain in men, but studies in this area are limited (n = 3). Moreover, whether hypohydration also affects pain in women has not been examined. In women, changes in the concentrations of reproductive hormones across menstrual phases may affect pain, as well as the regulation of body water. This indicates potential interactions between the menstrual phase and hypohydration on pain, but this hypothesis has yet to be tested. This review examined the literature concerning the effects of the menstrual phase and hypohydration on pain, to explore how these factors may interact to influence pain. Future research investigating the combined effects of hypohydration and menstrual phase on pain is warranted, as the findings could have important implications for the treatment of pain in women, interpretation of previous research and the design of future studies.