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Objective:To discuss the potential for adverse consequences that could arise from the quest to prolong the functional life span of the human ovary. Methods:A series of arguments are presented that: (a) question the dogma that monthly ovulatory menstrual cycles are critical for women’s health; (b) review adverse consequences of decades of menstrual cyclicity; (c) review the evidence for a longevity benefit of ovarian steroid hormone treatment after the age at natural menopause has been achieved; and (d) utilize a mathematical model of ovarian follicle loss over time to raise the possibility that current strategies directed at delaying menopause might well backfire and in fact cause a woman to have a prolonged menopause transition. Results:Regular, monthly menstrual cycles have not been the reality for women for most of history. Rather, when not pregnant, lactational amenorrhea and nutritionally based hypothalamic amenorrhea were the norm for reproductive-aged women. Moreover, monthly menstrual cycles cause substantial morbidity for women during their reproductive years. Providing steroid hormones after menopause has failed to demonstrate an increase in the female life span. Restoring ovarian follicles either surgically or medically has a high probability of causing women to spend more years of life in the menopause transition. Conclusions:Strategies to prevent or delay menopause would benefit from careful consideration of unintended consequences as they are implemented. Directing treatment trials to those with the greatest chance for benefit should be undertaken before adopting this type of treatment for a broader population.
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Parturitions, menopause and other physiological stressors are recorded in dental cementum microstructure
Abstract The life history pattern of recent humans is uniquely derived in many of its aspects including an extended post-reproductive lifespan combined with short interbirth intervals. A number of theories have been proposed to explain the evolution of this unusual pattern. However most have been difficult to test due to the fragmentary nature of the hominin fossil record and the lack of methods capable of inferring such later life history events. In search of a method we tested the hypothesis that the physiologically impactful events of parturition and menopause are recorded in dental cementum microstructure. We performed histomorphological analyses of 47 teeth from 15 individuals with known life history events and were able to detect reproductive events and menopause in all females. Furthermore, we found that other stressful events such as systemic illnesses and incarceration are also detectable. Finally, through the development of a novel analytical method we were able to time all such events with high accuracy (R-squared = 0.92).
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- Award ID(s):
- 2018357
- PAR ID:
- 10248330
- Date Published:
- Journal Name:
- Scientific Reports
- Volume:
- 10
- Issue:
- 1
- ISSN:
- 2045-2322
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1038/s41598-020-62177-7
