Life expectancy in France was below thirty in the late 1700s, but over the course of the next two and a half centuries it is expected to reach 82.5 by the year 2020. Although life expectancy has generally increased throughout France's history, there were several times where the rate deviated from its previous trajectory. The most noticeable changes were because of smallpox and influenza epidemics in the 1700s, medical advancements (such as vaccination and pasteurization) saw life expectancy increase in the 1800s, and then both World Wars and the epidemics that followed caused brief drops in the first half of the twentieth century.

A global phenomenon, known as the demographic transition, has seen life expectancy from birth increase rapidly over the past two centuries. In pre-industrial societies, the average life expectancy was around 24 years, and it is believed that this was the case throughout most of history, and in all regions. The demographic transition then began in the industrial societies of Europe, North America, and the West Pacific around the turn of the 19th century, and life expectancy rose accordingly. Latin America was the next region to follow, before Africa and most Asian populations saw their life expectancy rise throughout the 20th century.

For most of the world, throughout most of human history, the average life expectancy from birth was around 24. This figure fluctuated greatly depending on the time or region, and was higher than 24 in most individual years, but factors such as pandemics, famines, and conflicts caused regular spikes in mortality and reduced life expectancy. Child mortality The most significant difference between historical mortality rates and modern figures is that child and infant mortality was so high in pre-industrial times; before the introduction of vaccination, water treatment, and other medical knowledge or technologies, women would have around seven children throughout their lifetime, but around half of these would not make it to adulthood. Accurate, historical figures for infant mortality are difficult to ascertain, as it was so prevalent, it took place in the home, and was rarely recorded in censuses; however, figures from this source suggest that the rate was around 300 deaths per 1,000 live births in some years, meaning that almost one in three infants did not make it to their first birthday in certain periods. For those who survived to adolescence, they could expect to live into their forties or fifties on average. Modern figures It was not until the eradication of plague and improvements in housing and infrastructure in recent centuries where life expectancy began to rise in some parts of Europe, before industrialization and medical advances led to the onset of the demographic transition across the world. Today, global life expectancy from birth is roughly three times higher than in pre-industrial times, at almost 73 years. It is higher still in more demographically and economically developed countries; life expectancy is over 82 years in the three European countries shown, and over 84 in Japan. For the least developed countries, mostly found in Sub-Saharan Africa, life expectancy from birth can be as low as 53 years.

The fertility rate of a country is the average number of children that women from that country would have throughout their reproductive years. In France in 1800, the average woman of childbearing age would have 4.4 children over the course of their lifetime. The beginning of the nineteenth century was a tumultuous time in France's history, involving France's revolutionary period, as well as the Napoleonic Empire. In the first decade of the 1800s, the fertility rate dropped by 0.4, before dropping more slowly, by another 0.5 between 1810 and 1850. The fertility growth rate fluctuated slightly in the late 1800s, before dropping drastically in the early twentieth century, falling from an average of 3 children per woman to less than 1.7 in 1920. France's fertility rate reached this point as a result of the First World War, and the influenza epidemic (known as the Spanish Flu) that followed. The interwar period saw a slight increase in fertility rate, before it fell again in the Second World War. Similarly to other major European countries after the war, France experienced a baby boom in the two decades following the war, before dropping again into the 1980s. The fertility rate reached it's lowest point in the post-war period, falling to 1.7 in 1995, before increasing in more recent years.