 The middle of the 20th century was marked by a significant and persistent increase in fertility rates in many countries of the world, especially in the West , leading to those born during this baby boom being nicknamed the baby boomer generation . The term "baby boom " is often used to refer to this particular boom, generally considered to have started immediately after World War II, although some demographers place it earlier or during the war.  The boom coincided with a marriage boom. The increase in fertility was driven primarily by  decrease in childlessness and  increase in parity progression to a second child. In most of the Western countries, progression to a third child and beyond declined  which, coupled with aforementioned increase in transition to first and second child, resulted in higher homogeneity in family sizes. The baby boom was most prominent among educated and economically active women. The baby boom ended with the significant decline in fertility rates in the 1960s and 1970s which was later called the "baby bust " by demographers. upright=2.25|United States birth rate (births per 1000 population). Pre-2003 data came from: "Table 1-1. Live Births, Birth Rates, and Fertility Rates, by Race: United States, 1909-2003". Centers for Disease Control and Prevention (CDC). (Retrieved from: "Vital Statistics of the United States, 2003, Volume I, Natality". CDC.) Post-2003 data came from: "National Vital Statistics Reports" (8 December 2010). CDC. Volume 59, no. 1. The graph is an expanded SVG version of :File:U. S.BirthRate.1909.2003.png The United States Census Bureau defines baby boomers as those born between mid-1946 and mid-1964 (shown in red)."Fueled by Aging Baby Boomers, Nation's Older Population to Nearly Double in the Next 20 Years, Census Bureau Reports". United States Census Bureau. 6 May 2014. Australia and New Zealand The volume of baby boom was the largest in the world in New Zealand and second-largest in Australia. Like the US, the New Zealand baby boom was stronger among Catholics than Protestants. The author and columnist Bernard Salt places the Australian baby boom between 1946 and 1961.%DIFDELCMD < %DIFDELCMD < %%% United Kingdom In the United Kingdom the baby boom occurred in two waves. After a short first wave of the baby boom during the war and immediately after, peaking in 1946, the United Kingdom experienced a second wave during the 1960s, with a peak in births in 1964.Office for National Statistics Births in England and Wales: 2017 the wiggles Ireland The baby boom in Ireland began during the Emergency declared in the country during the Second World War. Laws on contraception were restrictive in Ireland, and the baby boom was more prolonged in this country. Secular decline of fertility began only in the 1970s and particularly after the legalization of contraception in 1979. The marriage boom was even more prolonged and did not recede until the 1980s. Western Europe France and Austria experienced the strongest baby booms in Europe. In contrast to most other countries, the French and Austrian baby booms were driven primarily by an increase in marital fertility. In the French case, pronatalist policies were an important factor in this increase. Weaker baby booms occurred in Germany, Switzerland, Belgium and the Netherlands . Southern Europe Baby boom was absent or not very strong in Italy, Greece, Portugal and Spain. There were however regional variations in Spain, with a considerable baby boom occurring in regions such as Catalonia. Eastern Europe There was a strong baby boom in Czechoslovakia, but it was weak or absent in Poland, Bulgaria, Russia, Estonia and Lithuania, partly as a result of the Soviet famine of 1946–47. Nordic countries The baby boom was very strong in Norway and Iceland, significant in Finland, moderate in Sweden and relatively weak in Denmark. 
upright=2.25|United States birth rate (births per 1000 population).Pre-2003 data came from: "Table 1-1. Live Births, Birth Rates, and Fertility Rates, by Race: United States, 1909-2003". Centers for Disease Control and Prevention (CDC). (Retrieved from: "Vital Statistics of the United States, 2003, Volume I, Natality". CDC.) Post-2003 data came from: "National Vital Statistics Reports" (8 December 2010). CDC. Volume 59, no. 1. The graph is an expanded SVG version of :File:U.S.BirthRate.1909.2003.png The US Census Bureau defines baby boomers as those born between mid-1946 and mid-1964 (shown in red)."Fueled by Aging Baby Boomers, Nation's Older Population to Nearly Double in the Next 20 Years, Census Bureau Reports". United States Census Bureau. 6 May 2014. The middle of the 20th century was marked by a significant and persistent increase in fertility rates in many countries of the world, especially in the West . The term baby boom is often used to refer to this particular boom, generally considered to have started immediately after World War II, although some demographers place it earlier or during the war. This terminology led to those born during this baby boom being nicknamed the baby boomer generation. The boom coincided with a marriage boom. The increase in fertility was driven primarily by a decrease in childlessness and an increase in parity progression to a second child. In most of the Western countries, progression to a third child and beyond declined , which, coupled with aforementioned increase in transition to first and second child, resulted in higher homogeneity in family sizes. The baby boom was most prominent among educated and economically active women. The baby boom ended with a significant decline in fertility rates in the 1960s and 1970s , later called the baby bust by demographers. Europe France and Austria experienced the strongest baby booms in Europe. In contrast to most other countries, the French and Austrian baby booms were driven primarily by an increase in marital fertility. In the French case, pronatalist policies were an important factor in this increase. Weaker baby booms occurred in Germany, Switzerland, Belgium and the Netherlands. %DIFDELCMD < %DIFDELCMD < %%% In the United Kingdom the baby boom occurred in two waves. After a short first wave of the baby boom during the war and immediately after, peaking in 1946, the United Kingdom experienced a second wave during the 1960s, with a peak in births in 1964.Office for National Statistics Births in England and Wales: 2017 The baby boom in Ireland began during the Emergency declared in the country during the Second World War. Laws on contraception were restrictive in Ireland, and the baby boom was more prolonged in this country. Secular decline of fertility began only in the 1970s and particularly after the legalization of contraception in 1979. The marriage boom was even more prolonged and did not recede until the 1980s. The baby boom was very strong in Norway and Iceland, significant in Finland, moderate in Sweden and relatively weak in Denmark . Baby boom was absent or not very strong in Italy, Greece, Portugal and Spain. There were however regional variations in Spain, with a considerable baby boom occurring in regions such as Catalonia. There was a strong baby boom in Czechoslovakia, but it was weak or absent in Poland, Bulgaria, Russia, Estonia and Lithuania, partly as a result of the Soviet famine of 1946–47. Oceania The volume of baby boom was the largest in the world in New Zealand and second-largest in Australia. Like the US, the New Zealand baby boom was stronger among Catholics than Protestants. The author and columnist Bernard Salt places the Australian baby boom between 1946 and 1961.
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upright=2.25|United States birth rate (births per 1000 population).Pre-2003 data came from: "Table 1-1. Live Births, Birth Rates, and Fertility Rates, by Race: United States, 1909-2003". Centers for Disease Control and Prevention (CDC). (Retrieved from: "Vital Statistics of the United States, 2003, Volume I, Natality". CDC.) Post-2003 data came from: "National Vital Statistics Reports" (8 December 2010). CDC. Volume 59, no. 1. The graph is an expanded SVG version of :File:U.S.BirthRate.1909.2003.png The US Census Bureau defines baby boomers as those born between mid-1946 and mid-1964 (shown in red)."Fueled by Aging Baby Boomers, Nation's Older Population to Nearly Double in the Next 20 Years, Census Bureau Reports". United States Census Bureau. 6 May 2014.
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, leading to those born during this baby boom being nicknamed the baby boomer generation
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"baby boom "
baby boom
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This terminology led to those born during this baby boom being nicknamed the baby boomer generation.
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"baby bust "
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upright=2.25|United States birth rate (births per 1000 population). Pre-2003 data came from: "Table 1-1. Live Births, Birth Rates, and Fertility Rates, by Race: United States, 1909-2003". Centers for Disease Control and Prevention (CDC). (Retrieved from: "Vital Statistics of the United States, 2003, Volume I, Natality". CDC.) Post-2003 data came from: "National Vital Statistics Reports" (8 December 2010). CDC. Volume 59, no. 1. The graph is an expanded SVG version of :File:U. S.BirthRate.1909.2003.png The United States Census Bureau defines baby boomers as those born between mid-1946 and mid-1964 (shown in red)."Fueled by Aging Baby Boomers, Nation's Older Population to Nearly Double in the Next 20 Years, Census Bureau Reports". United States Census Bureau. 6 May 2014.
Europe France and Austria experienced the strongest baby booms in Europe. In contrast to most other countries, the French and Austrian baby booms were driven primarily by an increase in marital fertility. In the French case, pronatalist policies were an important factor in this increase. Weaker baby booms occurred in Germany, Switzerland, Belgium and the Netherlands.
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Australia and New Zealand The volume of baby boom was the largest in the world in New Zealand and second-largest in Australia. Like the US, the New Zealand baby boom was stronger among Catholics than Protestants.
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The author and columnist Bernard Salt places the Australian baby boom between 1946 and 1961.
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United Kingdom
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the wiggles
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Ireland
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Western Europe France and Austria experienced the strongest baby booms in Europe. In contrast to most other countries, the French and Austrian baby booms were driven primarily by an increase in marital fertility. In the French case, pronatalist policies were an important factor in this increase. Weaker baby booms occurred in Germany, Switzerland, Belgium and the Netherlands
The baby boom was very strong in Norway and Iceland, significant in Finland, moderate in Sweden and relatively weak in Denmark
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Southern Europe
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Eastern Europe
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Nordic countries The
Oceania The volume of
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very strong in Norway and Iceland, significant in Finland, moderate in Sweden and relatively weak in Denmark.
the largest in the world in New Zealand and second-largest in Australia. Like the US, the New Zealand baby boom was stronger among Catholics than Protestants.
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The author and columnist Bernard Salt places the Australian baby boom between 1946 and 1961.