Advanced maternal age
Encyclopedia
Advanced maternal age is defined as an increase in the age at which women give birth to their first child, is now a widespread, and indeed near universal, phenomenon across the OECD countries.
In Western, Northern, and Southern Europe, first-time mothers are on average 26 to 29 years old, up from 23 to 25 years at the start of the 1970s. In a number of European countries (Spain), the mean age of women at first childbirth has now even crossed the 30 year threshold.
This process is not restricted to Europe. Asia
, Japan
and the United States
are all seeing average age at first birth on the rise, and increasingly the process is spreading to countries in the developing world like China
, Turkey
and Iran
. In the U.S., the age of first childbirth was 25 in 2006.
This association has now become especially clear since the postponement of first births in a number of countries has now continued unabated for more than three decades, and has become one of the most prominent characteristics of fertility patterns in developed societies. A variety of authors (in particular Lesthaeghe) have argued that fertility postponement constitutes the ‘hallmark’ of what has become known as the second demographic transition.
Others have proposed that the postponement process itself constitutes a separate 'third transition' (Kohler
, Billari, and Ortega
). On this latter view modern developed societies exhibit a kind of dual fertility regime, with the majority of births being concentrated either among very young or increasingly older mothers. This is sometimes known as the 'rectangularisation' of fertility patterns.
A focus on the timing of first birth is important for understanding the overall trends towards later childbearing. While second and higher-order births are also being postponed, such postponement is mostly a consequence of first birth postponement rather than a manifestation of change in birth intervals. It is worth stressing that the determinants of delayed parenthood are frequently identical with the determinants of low fertility and non-parenthood.
A woman's risk of having a baby with chromosomal abnormalities increases with her age. Down syndrome
is the most common chromosomal birth defect, and a woman's risk of having a baby with Down syndrome is:
exhibit an ever-increasing demand for highly educated and flexible workers. For the individual, the pursuit of higher education
constitutes the principal pathway for finding a stable job, securing a higher salary, and for increasing career prospects generally. As a result most young people remain enrolled in some form of education well into early adulthood.
The anticipated number of years post compulsory education is now as high as 8.5 years in France, and up to half of all those in the 20-24 age group (and even between 50 and 55% in Denmark
, Finland
, and France
) are enrolled in full-time or part-time studies. Women have especially benefited from this development and now form more than half of the graduate and postgraduate students in a majority of European countries. Such educational expansion evidently has a direct implication for fertility trends.
Traditionally, employment and motherhood were seen as incompatible roles, and Gary Becker’s argument that the increasing gender equality which gives rise to greater earning power for women increases both their labor force participation and the opportunity costs of childbearing, consequently reducing the demand for children. Recent studies, however, have increasingly found that the relationship between labor force participation and fertility is not a straightforward one and may be filtered through a number of additional factors. Looked at dynamically it is not hard to argue that compatibility between family life and labor force participation, as impacted by societal differences, cohort membership, age, and education all serve to modify this relationship.
In the past, many women became employed, but with the mindset that when they married or became pregnant they would withdraw from the workforce. However, more recently women have begun to enter the workforce with a long-term mindset where they invest more and instead of working intermittent jobs, plan a career. Therefore, with this mindset, women tend to marry later and give birth at more advanced ages in order to first put together a career.
Clearly both individual and societal conditions associated with uncertainty have a strong impact on fertility decisions. Mills and Blossfeld distinguish between (1) economic uncertainty, related to the “economic precariousness of an individual’s employment and educational enrollment circumstances,” (2) temporal uncertainty, and (3) employment relationship uncertainty, reflecting the type and
precariousness of the employment contract.
In the Mills-Blossfeld framework, being unemployed leads to a high level of an individual’s economic uncertainty, whereas rising unemployment rates could lead to higher temporal uncertainty. Young adults are increasingly susceptible to all forms of uncertainty, especially with regards to their employment situation, which has a disproportionate impact on disadvantaged—especially less educated—social groups.
In addition, the rapid pace of change, the unpredictability of social and economic developments, and the overflow of information create uncertainty about possible behavioural outcomes as well as about the probability of these outcomes, and about the amount of information to be collected for a particular decision. Unsurprisingly these authors suggest that the rapid rise of globalisation has been a key factor associated with increasing the levels of each of the these three types of uncertainty.
In Western, Northern, and Southern Europe, first-time mothers are on average 26 to 29 years old, up from 23 to 25 years at the start of the 1970s. In a number of European countries (Spain), the mean age of women at first childbirth has now even crossed the 30 year threshold.
This process is not restricted to Europe. Asia
Asia
Asia is the world's largest and most populous continent, located primarily in the eastern and northern hemispheres. It covers 8.7% of the Earth's total surface area and with approximately 3.879 billion people, it hosts 60% of the world's current human population...
, Japan
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
and the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
are all seeing average age at first birth on the rise, and increasingly the process is spreading to countries in the developing world like China
China
Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...
, Turkey
Turkey
Turkey , known officially as the Republic of Turkey , is a Eurasian country located in Western Asia and in East Thrace in Southeastern Europe...
and Iran
Iran
Iran , officially the Islamic Republic of Iran , is a country in Southern and Western Asia. The name "Iran" has been in use natively since the Sassanian era and came into use internationally in 1935, before which the country was known to the Western world as Persia...
. In the U.S., the age of first childbirth was 25 in 2006.
Advanced maternal age and low fertility
Having children later was not exceptional in the past, when families were larger and women often continued bearing children until the end of their reproductive age. What is so radical about this recent transformation is that it is the age at which women give birth to their first child which is becoming comparatively high, leaving an ever more constricted window of biological opportunity for second and subsequent children should they be desired. Unsurprisingly, high first-birth ages and rapid rates of birth postponement are associated with the arrival of low, and lowest-low fertility.This association has now become especially clear since the postponement of first births in a number of countries has now continued unabated for more than three decades, and has become one of the most prominent characteristics of fertility patterns in developed societies. A variety of authors (in particular Lesthaeghe) have argued that fertility postponement constitutes the ‘hallmark’ of what has become known as the second demographic transition.
Others have proposed that the postponement process itself constitutes a separate 'third transition' (Kohler
Kohler
Kohler is a family name of German origin. The name was first found in Saxony. It means, "Charcoal burner" so the first "Kohlers" were most likely of that occupation.-People:*Alan Kohler, Australian journalist*Herbert Kohler, Jr., businessman...
, Billari, and Ortega
Ortega
Ortega is a Spanish surname. In the 9th century a Saint Raymundo Ortega of Bejar was recorded to be in Salamanca, Spain. A baptismal record in 1570 records a de Ortega "from the village of Ortega". There were several villages of this name in Spain...
). On this latter view modern developed societies exhibit a kind of dual fertility regime, with the majority of births being concentrated either among very young or increasingly older mothers. This is sometimes known as the 'rectangularisation' of fertility patterns.
A focus on the timing of first birth is important for understanding the overall trends towards later childbearing. While second and higher-order births are also being postponed, such postponement is mostly a consequence of first birth postponement rather than a manifestation of change in birth intervals. It is worth stressing that the determinants of delayed parenthood are frequently identical with the determinants of low fertility and non-parenthood.
Risk of birth defects
Down syndrome
Down syndrome, or Down's syndrome, trisomy 21, is a chromosomal condition caused by the presence of all or part of an extra 21st chromosome. It is named after John Langdon Down, the British physician who described the syndrome in 1866. The condition was clinically described earlier in the 19th...
is the most common chromosomal birth defect, and a woman's risk of having a baby with Down syndrome is:
- At age 25, 1 in 1,250
- At age 30, 1 in 1,000
- At age 35, 1 in 400
- At age 40, 1 in 100
- At 45, 1 in 30
- At 49, a 1 in 10
Explanations for birth postponement
A variety of explanations have been offered as to why young people postpone parenthood.Increase in educational levels
In the first case such delay is normally associated with increasing levels of education. Post-industrial economiesPost-industrial economy
A post-industrial economy refers to a period of growth within an industrialized economy or nation in which the relative importance of manufacturing lessens and that of services, information, and research grows.Such economies are often marked by:...
exhibit an ever-increasing demand for highly educated and flexible workers. For the individual, the pursuit of higher education
Higher education
Higher, post-secondary, tertiary, or third level education refers to the stage of learning that occurs at universities, academies, colleges, seminaries, and institutes of technology...
constitutes the principal pathway for finding a stable job, securing a higher salary, and for increasing career prospects generally. As a result most young people remain enrolled in some form of education well into early adulthood.
The anticipated number of years post compulsory education is now as high as 8.5 years in France, and up to half of all those in the 20-24 age group (and even between 50 and 55% in Denmark
Denmark
Denmark is a Scandinavian country in Northern Europe. The countries of Denmark and Greenland, as well as the Faroe Islands, constitute the Kingdom of Denmark . It is the southernmost of the Nordic countries, southwest of Sweden and south of Norway, and bordered to the south by Germany. Denmark...
, Finland
Finland
Finland , officially the Republic of Finland, is a Nordic country situated in the Fennoscandian region of Northern Europe. It is bordered by Sweden in the west, Norway in the north and Russia in the east, while Estonia lies to its south across the Gulf of Finland.Around 5.4 million people reside...
, and France
France
The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...
) are enrolled in full-time or part-time studies. Women have especially benefited from this development and now form more than half of the graduate and postgraduate students in a majority of European countries. Such educational expansion evidently has a direct implication for fertility trends.
Employment and motherhood
A second explanation centres around the potential conflict which young women face between employment and motherhood. This conflict which is fuelled by rapidly increasing educational level and labor force participation among women, constitutes one of the most widely debated issues in contemporary fertility research.Traditionally, employment and motherhood were seen as incompatible roles, and Gary Becker’s argument that the increasing gender equality which gives rise to greater earning power for women increases both their labor force participation and the opportunity costs of childbearing, consequently reducing the demand for children. Recent studies, however, have increasingly found that the relationship between labor force participation and fertility is not a straightforward one and may be filtered through a number of additional factors. Looked at dynamically it is not hard to argue that compatibility between family life and labor force participation, as impacted by societal differences, cohort membership, age, and education all serve to modify this relationship.
In the past, many women became employed, but with the mindset that when they married or became pregnant they would withdraw from the workforce. However, more recently women have begun to enter the workforce with a long-term mindset where they invest more and instead of working intermittent jobs, plan a career. Therefore, with this mindset, women tend to marry later and give birth at more advanced ages in order to first put together a career.
Insecurity
As much as labor force participation per-se, security of employment is thought to be important, and the widespread presence of part-time and temporary employment at the younger ages are thought to persuade many to delay. This however is not an unequivocal view, since the availability of part-time employment may be thought to act in a pro-natal direction, making motherhood and employment continuity possible, and it may be rather the employment stability of the father which is the key factor.Clearly both individual and societal conditions associated with uncertainty have a strong impact on fertility decisions. Mills and Blossfeld distinguish between (1) economic uncertainty, related to the “economic precariousness of an individual’s employment and educational enrollment circumstances,” (2) temporal uncertainty, and (3) employment relationship uncertainty, reflecting the type and
precariousness of the employment contract.
In the Mills-Blossfeld framework, being unemployed leads to a high level of an individual’s economic uncertainty, whereas rising unemployment rates could lead to higher temporal uncertainty. Young adults are increasingly susceptible to all forms of uncertainty, especially with regards to their employment situation, which has a disproportionate impact on disadvantaged—especially less educated—social groups.
In addition, the rapid pace of change, the unpredictability of social and economic developments, and the overflow of information create uncertainty about possible behavioural outcomes as well as about the probability of these outcomes, and about the amount of information to be collected for a particular decision. Unsurprisingly these authors suggest that the rapid rise of globalisation has been a key factor associated with increasing the levels of each of the these three types of uncertainty.
Changes in interpregnancy interval
Kalberer et al. have shown that despite the older maternal age at birth of the first child, the time span between the birth of the first and the second child (= interpregnancy interval) decreased over the last decades. If purely biological factors were at work here, it could be argued that interpregnancy interval should have increased, as fertility declines with age, which would make it harder for the woman to get a second child after postponed birth of the first one. This not being the case shows that sociologic factors (see above) prime over biological factors in determining interpregnancy interval.See also
- Age at first marriageAge at first marriageThis is an incomplete list of the average ages of people when they first marry in various countries. This list is current , and does not treat the topic in history....
- Childlessness
- Paternal age effectPaternal age effectThe paternal age effect can refer to the statistical relationships of: a man's age to sperm and semen abnormalities; a man's age to his fertility; a man's age to adverse pregnancy outcomes in his female partner ; a father's age at the birth of his offspring on the probability of an adverse...
- Teenage pregnancyTeenage pregnancyTeenage pregnancy is a pregnancy of a female under the age of 20 when the pregnancy ends. It generally refers to a female who is unmarried and usually refers to an unplanned pregnancy...
Further reading
- Hofmeister, Heather; Mills, Melinda; Blossfeld, Hans-Peter (2003), Globalization, Uncertainty and Women’s Mid-Career Life Courses: A Theoretical Framework. University of Bamberg, Working Papers PDF
- Lesthaeghe, R. and K. Neels. 2002. “From the first to the second demographic transition: An interpretation of the spatial continuity of demographic innovation in France, Belgium and Switzerland”. European Journal of Population 18 (4): 325-360.
- Kohler, H.P., F. C. Billari, and J. A. Ortega. 2002. “The emergence of lowest-low fertility in Europe during the 1990s”. Population and Development Review 28 (4): 641-680.
- Gavrilov, L.A., Gavrilova, N.S. Human longevity and parental age at conception. In: J.-M.Robine, T.B.L. Kirkwood, M. Allard (eds.) Sex and Longevity: Sexuality, Gender, Reproduction, Parenthood, Berlin, Heidelberg: Springer-Verlag, 2000, 7-31.
- Gavrilov, L.A., Gavrilova, N.S. Parental age at conception and offspring longevity. Reviews in Clinical Gerontology, 1997, 7: 5-12.
External links
- The Fertility Bust, Charlemagne, The Economist, February 9 2006
- Low and Lowest-Low Fertility in Europe: Causes, Implications and Policy Options. By H-P Kohler, F.C. Billari and J.A Ortega. University of Pennsylvania, 2005.
- Postponement of childbearing and low fertility in Europe Power Point presentation by Tomas Sobotka
- InterNational Council on Infertility Information Dissemination