The Implications of Reproductive Aging for the Health, Vitality, and Economic Welfare of Human Societies

Abstract

Context: Powerful demographic trends toward reproductive aging of human populations, older age at first childbirth, and lower birth rates will profoundly influence the health, vitality, and economies of human societies and deserve greater attention in health policy and research.

Evidence acquisition: Information on birth rates, fertility rates, and outcomes of assisted reproductive technologies were obtained from databases of government agencies (census data, Centers for Disease Control and Prevention).

Evidence synthesis: Fecundity declines with advancing age, especially in women >35 years and men >50 years. Advanced parental age adversely affects pregnancy outcomes for the mother and the offspring and increases the offspring's risk of chromosomal disorders, neurodegenerative diseases, and birth defects. Because of increased life expectancy, today people will spend a major portion of life in a period of reproductive senescence; diseases associated with reproductive senescence will influence the health and well-being of middle-aged and older adults. Inversion of the population age pyramid will affect health care costs, retirement age, generational distribution of wealth, and the vitality of societies. Actions can be taken to mitigate the societal consequences of these trends. An educational campaign to inform young people about the trade-offs associated with postponement of childbirth will enable them to make informed choices. Some repositioning of research agenda and health care policies is needed to address the public health threat posed by reproductive aging.

Conclusion: The consequences of low fertility rates and delayed parenthood on our nation's health, vitality, and economic growth should be considered when crafting research, health, and economic policies.

Figure 1.

Birth rates per 1000 population, mean age of mother at first childbirth, and proportion of infants born in the United States to women older than 35 y of age since 1970. The birth rate per 1000 population declined from 18.4 in 1970 to 11.8 in 2017 (black circles). The mean age of mothers at first childbirth increased from 21.4 y in 1970 to 26.6 y in 2016 (blue diamonds). The proportion of all infants born in the United States to mothers older than 35 y increased from 4.6% in 1970 to 14.9% in 2012 (red triangles). For 1990 through 2017, rates are estimated as of July 1; for 1970 and 1980, rates are estimated as of April 1 and are redrawn from Centers for Disease Control and Prevention data (1).