Biochemistry of the menopause

Abstract

The life of a human female is characterized from teenage years by monthly menstruation which ceases (the menopause) typically between the age of 40 and 60 years. The potential for reproduction declines and ceases as the ovaries become depleted of follicles. A transition period in mid-life, for 2 to 10 years, when menstruation is less regular is called the perimenopause. The menopause is associated with a significant decline in plasma concentrations of sex hormones, an increase in the concentrations of the gonadotrophins and changes in other hormones such as the inhibins. These changes are superimposed with effects of aging, social and metabolic factors, daily activity and well-being. Although the menopause is entirely natural, in some cases ovarian failure can occur earlier than usual; this is pathological and warrants careful biochemical investigations to distinguish it from conditions causing infertility. Elderly females are affected by a range of clinical disorders including endocrine, cardiovascular, skeletal, urogenital tract and immunological systems, body mass, vasomotor tone, mood and sleep pattern. Reference intervals for many diagnostic biochemical tests for the menopause need to be used when interpreting results in clinical investigations for patient management. The standardization and harmonization of assays are being addressed. Many women now choose to develop their career before bearing children, and the health service has had to change services around this. This review does not cover screening for and tests during pregnancy. The review is timely since the population is aging and there will be more demand on healthcare services.

Age of Natural Menopause and Related Factors among the Tabari Cohort

“…Influence of menopause on functions of endocrine, cardiovascular, skeletal, immune, and genitourinary systems has been reported previously [2]. The age of menopause is affected by many factors including genetic factors, obesity, alcohol consumption, social levels, ethnicity, education, diet, vitamin D and calcium intake, menarche age, long-term menstrual cy-cles, oral contraceptive use, and exposure to pesticides [1][2][3][4]. The World Health Organization has stated that by the year 2030, globally, there will be more than 1.2 billion women suffering from menopause along with obesity and high body mass index (BMI) and moreover it has been reported that every year 47 million women enter this stage of their lives [1].…”

“…The mean age of menopause was 47.9 ± 5.7 years with a minimum of 23 and a maximum of 64 years. The prevalence of normal menopause was 77.7% (2,140), and the prevalence of induced menopauses (due to surgery) was 22.3% (613). The mean age of natural and induced menopause was 49.2 ± 4.7 and 43.2 ± 6.4, respectively (P = 0.001).…”

“…Level of estrogen decreases and eventually combines with menstrual cessation [1]. Influence of menopause on functions of endocrine, cardiovascular, skeletal, immune, and genitourinary systems has been reported previously [2]. The age of menopause is affected by many factors including genetic factors, obesity, alcohol consumption, social levels, ethnicity, education, diet, vitamin D and calcium intake, menarche age, long-term menstrual cy-cles, oral contraceptive use, and exposure to pesticides [1][2][3][4].…”

Hepcidin is an endogenous protective factor for osteoporosis by reducing iron levels

“…Menopause is a naturally occurring phenomenon that affects most women above the approximate age of 52 years. The menopause-associated physiological exhaustion of ovarian function increases reproductive, cardiovascular and mental impairments and cancer (Pluchino et al 2011, Cutler et al 2015, Gong et al 2016, Honour 2018). Furthermore, the musculoskeletal system is also deeply affected by menopause (Cauley 2015, Sullivan et al 2015.…”

The Age of Natural Menopause and Related Factors among the Population of the Tabari Cohort.

“…Influence of menopause on functions of endocrine, cardiovascular, skeletal, immune and genitourinary systems has been reported previously [2].…”