90 Menopause and andropause

Learning Objectives

After reading this section you should be able to-

  • DefineĀ  menopause and and describe the physiological changes associated with menopause
  • Compare and contrast menopause and andropause

Menopause

A well-known example of the aging process affecting an endocrine gland is menopause and the decline of ovarian function. Menopause marks the end of a woman’s reproductive years, typically occurring between the ages of 45 and 55. It is defined as the cessation of menstrual cycles for 12 consecutive months. This natural biological process signifies the end of ovarian function, leading to a significant decline in the production of key hormones, primarily estrogen and progesterone.

Physiological Changes Associated with Menopause:

  1. Hormonal Changes: The most notable change during menopause is the reduction in estrogen and progesterone levels. This hormonal decline is due to the ovaries becoming less responsive to gonadotropins (LH and FSH), which regulate reproductive function.
  2. Reproductive Changes: As hormone levels drop, the ovaries gradually decrease in size and weight. This process leads to the cessation of ovulation and menstrual periods, marking the end of a woman’s fertility.
  3. Vasomotor Symptoms: Many women experience hot flashes and night sweats, which are sudden feelings of warmth, often accompanied by redness and sweating. These symptoms result from fluctuating hormone levels affecting the body’s temperature regulation.
  4. Urogenital Atrophy: Lower estrogen levels can cause thinning and drying of the vaginal and urethral tissues, leading to discomfort, dryness, and increased susceptibility to infections.
  5. Bone Density Changes: Estrogen plays a crucial role in maintaining bone density. Its decline during menopause can accelerate bone loss, increasing the risk of osteoporosis and fractures.
  6. Cardiovascular Health: Post-menopausal women face a higher risk of cardiovascular diseases, such as atherosclerosis and hyperlipidemia, partly due to the protective effects of estrogen on the cardiovascular system diminishing.
  7. Psychological and Cognitive Changes: Mood swings, depression, and cognitive changes such as memory loss and difficulty concentrating are common during menopause. These symptoms may be linked to hormonal fluctuations and sleep disturbances.

Andropause

Testosterone levels also decline with age, a condition called andropause (or viropause); however, this decline is much less dramatic than the decline of estrogens in women. Andropause, also known as male menopause or viropause, refers to the gradual decline in testosterone levels that typically occurs in men as they age, usually starting around the age of 40. Unlike menopause in women, which involves a rapid decline in reproductive hormones and a definitive end to fertility, andropause is characterized by a slow and steady decrease in testosterone levels. This decline can affect various bodily functions, but it does not result in the complete loss of fertility. Men experiencing andropause may notice changes in physical, emotional, and sexual health, though the symptoms are often more subtle and develop gradually over time.

Physiological Changes Associated with Andropause:

The physiological changes associated with andropause stem primarily from the reduction in testosterone production. One of the most noticeable effects is a decrease in muscle mass and strength, which can lead to a reduction in overall physical fitness and an increase in body fat. This change in body composition is often accompanied by a decrease in bone density, increasing the risk of osteoporosis and fractures. Additionally, men may experience a decline in libido and sexual function, including erectile dysfunction and reduced sperm quality and motility, though they often retain the ability to father children.

Hormonal changes during andropause also impact mood and cognitive function. Men may experience increased fatigue, depression, irritability, and difficulty concentrating. Sleep disturbances, such as insomnia or poor sleep quality, are also common. Cardiovascular health can be affected as well, with changes in lipid profiles leading to an increased risk of atherosclerosis and other cardiovascular diseases. The overall decline in testosterone can also result in a reduced sense of well-being and lower energy levels, making daily activities and physical exercise more challenging. Understanding these physiological changes can help in managing symptoms and improving the quality of life for men undergoing andropause.

Comparison between menopause and andropause

While menopause and andropause both involve age-related hormonal changes, there are significant differences in their onset, progression, and effects on reproductive function.

Menopause

  1. Onset and Duration: Menopause typically occurs in women between 45 and 55 years of age and is marked by a clear end point: the cessation of menstrual periods.
  2. Hormonal Changes: There is a rapid and significant decline in estrogen and progesterone levels due to the decreased function of the ovaries.
  3. Reproductive Function: Menopause results in the complete loss of fertility. Women no longer ovulate or menstruate.
  4. Symptoms: Menopausal symptoms can be severe and include hot flashes, night sweats, vaginal dryness, and mood changes. Long-term effects include an increased risk of osteoporosis and cardiovascular diseases.

Andropause

  1. Onset and Duration: Andropause, or the gradual decline in testosterone levels, typically begins around age 40 and progresses slowly over decades.
  2. Hormonal Changes: The decrease in testosterone is much less dramatic and more gradual compared to the hormonal changes in menopause. Testosterone levels decline by about 1% per year after the age of 30-40.
  3. Reproductive Function: Unlike menopause, andropause rarely leads to complete infertility. Men often maintain the ability to produce sperm and father children well into old age, though the quality and motility of sperm may decline.
  4. Symptoms: Symptoms of andropause are often subtle and can include reduced libido, erectile dysfunction, fatigue, depression, and reduced muscle mass and strength. These changes are generally less pronounced than the symptoms of menopause.

Key Comparisons

  • Severity of Hormonal Decline: Menopause involves a rapid and significant drop in estrogen and progesterone, whereas andropause involves a slow, gradual decline in testosterone.
  • Reproductive Impact: Menopause results in complete loss of fertility, while andropause rarely affects sperm production to the point of infertility.
  • Symptoms and Health Effects: Both conditions can lead to decreased bone density and changes in cardiovascular health, but menopause symptoms tend to be more severe and disruptive. Andropause symptoms are typically less pronounced and develop more gradually.

In summary, while both menopause and andropause involve hormonal changes and aging, their effects on the body, reproductive function, and symptom severity differ significantly.

Adapted from Anatomy & Physiology by Lindsay M. Biga et al, shared under a Creative Commons Attribution-ShareAlike 4.0 International License, chapter 27.

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