Factors affecting age of onset of menopause and determination of quality of life in menopause

March 2015
Turk J Obstet Gynecol

Abstract

Menopause is a process in the climacteric period, characterized by a reduction in ovarian activity, a fall in the fertility rate, and a range of symptoms including irregular menstruation intervals. Most women enter menopause in their 40s, but this can vary from one individual to another.

Although there are many factors affecting the age of menopause onset, there is no general agreement on them. Studies have shown many factors to affect the age of menopause, such as the mother’s age at menopause, the age at menarche, gestational age, use of oral contraceptives, irregular menstrual cycle, number of pregnancies, body mass index, use of tobacco and alcohol, physical activity, unilateral oophorectomy, serum lead levels, consumption of polyunsaturated fat, socioeconomic status and educational level.

During this period, hormonal and biochemical changes give rise to various symptoms in the woman’s body. In menopause period, physical, psychological, social and sexual changes have a negative effect on quality of life in women. Recently, different measures have been used to assess women’s quality of life in this period of change. The purpose of this review was to examine the factors affecting the onset age of menopause and the measures of quality of life related to menopause.

Keywords: Menopausal age, affecting factors, menopause specific quality of life scales

INTRODUCTION

Scientific and technological advances have lengthened the span of life and led to an increase in world’s elderly population. While in 1000 B.C., average life expectancy for women is estimated to have been 28 years of age, today this figure has reached to 8th decade of life(1). According to 2013 world population data, life expectancy for newborn girls is 73 years in average around the world and 78 in Turkey(2).

The report of the Menopause and Osteoporosis Association of Turkey, published in 2002, reveals that the average age of menopause is 47(3). Accordingly, it can be said that a woman who is expected to live 78 years spends a significant part of her life in menopause.

The word “menopause” derives from the Greek “men” (month or monthly cycle) and “pausis” (end, stop), i.e., “the cessation of monthly cycle.” The World Health Organization (WHO) describes it as the permanent cessation of menstruation as a result of the loss of ovarian follicular function(4,5). The menopause signals are a reduction of ovarian activity and a fall in fertility. With the appearance of various symptoms and irregular menstrual periods, it is a characteristic phase of the climacteric stage. The hormonal and biochemical changes that occur in this period lead to various symptoms in woman’s body(6).

THE ONSET AGE OF MENOPAUSE AND INFLUENCING FACTORS

The transition from a woman’s fertile period to the period in which the ovaries begin to lose their function is achieved gradually. It is for this reason that it is difficult to set down a definite age at which menopause will begin for every woman. This period generally commences in the fourth decade of life and varies from one woman to another.

Community-based studies indicate that the distribution of menopausal age displays a bell curve that ranges from age 40, ending around the age of 54, generally clustering around the ages 45-55(7,8,9,10,11,12,13,14,15,16,17,18,19,21,22,23,24,25). In one study, the average age of menopause has been reported as 54 in Europe, 51.4 in North America, 48.6 in Latin America and 51.1 in Asia(20).

Although there are many factors that influence the onset of menopause, there is no consensus as to whether these factors are definitive in all women (Table 1). Studies show that the onset age of menopause is affected by the age at the first menstrual period, the use of oral contraceptives, the number of pregnancies experienced, Body Mass Index (BMI), smoking, drinking alcoholic beverages, physical activity, blood lead levels and other factors(26,27,28,29,30,31,32,33,34). It is believed that in about 50% of women, genetic factors play a role in determining the age of onset of menopause(26). Women whose mothers entered menopause at an early age are at a high risk of early onset menopause(27).

In many studies, it has been shown that women who smoke enter menopause at earlier ages than non-smokers(30,31,32,33,35,36,37,38). It has been observed that women who smoke 14 or more cigarettes a day enter menopause 2.8 years earlier than women who do not smoke(39). Women who do not drink alcoholic beverages have been found to enter menopause at earlier ages than women who do consume alcoholic drinks(31,33,37,38).

While heavy physical activity is associated with early menopause(19,33), light physical activity delays menopause to later ages(31,40). A high consumption of polyunsaturated fats accelerates the onset of menopause while a high consumption of total calories, fruits and protein delays it(32,33). A high BMI has been found to be associated with a higher menopause onset age(19,28,30,31,38,41,42). It has been found that women with hypertension and a low exposure to the sun throughout the life enter menopause at earlier ages(19).