“It doesn't matter if we Spaniards do not have enough children, as long as foreign migrants come to Spain and have kids here,” the head of a major conservative Spanish think tank said to me a couple of years ago. I had suggested to him that the center-right Partido Popular—now the governing party in Spain—promote pro-natal policies.

But can immigration really make up for Spain’s growing birth deficit? Since 2011, when we had our conversation, both Spaniards and migrants have had fewer children each year. In part because of the ongoing economic recession, there were 10% fewer children born in 2013 than in 2011. Moreover, more people migrated out of Spain than migrated into it during this period. The net migration flow was negative, not positive.

Tylenol is great for relieving the pain of a headache, but it won’t cure a brain tumor. In fact, by masking the pain, it might stop us from finding out that we have a tumor and seek treatment for it. It might, in this way, actually kill us.

Many Europeans view immigration the way that people with a headache view Tylenol. The immigrants flooding into Europe mask the pain of the aging native population with its huge baby deficit. It disguises the ugly core demographic numbers, and gives politicians and the public an excuse to avoid taking the real steps necessary to avoid committing demographic suicide.

Europe and Japan are the frontrunners in this race to oblivion. Both have populations that are dramatically shrinking and aging. Low birth rates and increased life expectancy are both responsible, but what the demographers call “lowest low fertility” accounts for the bulk of the problem.

In the official published statistics, foreign immigrants and their locally born children partially cover up a very inconvenient truth: native European populations are ageing at historically unprecedented speeds. They are shrinking, or on the verge of shrinking, because two generations of Europeans have failed to have enough children to replace themselves. Foreign migrants partially mask this pain, making European (and US) demographic statistics look better than they otherwise would. Immigrants provide:

More people: this is especially valuable in countries whose native population is already decreasing. For instance, the population of Spain was about to start shrinking 15 years ago, but 6 million foreign immigrants, who had over 1 million children, forestalled this. As a result, the country’s population grew by 15%, instead of shrinking.

A significant number of additional births: Immigrants have high birth rates, accounting for from 15% to 40% of all children born in European countries. For instance, the mothers of over 35% of all the babies born in Switzerland were born abroad. This number is 30% in Belgium and Austria, 25% in the UK, Sweden, and Norway, 22% in Spain, and 20% in France. In Spain, there are provinces where 35% - 40% of babies come from foreign-born parents, often Morocco.

“Natural population change” improved: The difference between births and deaths—the so-called “natural population change”—is generally increased by migrants. They add a significant number of births, but die proportionally less than natives. This is because they arrive in their new country when they are 20 to 50 years old, and their mortality rates are much lower than those of 65 years and over. This contribution is especially valuable in countries like Germany, Italy, Spain, Austria or Switzerland, whose native populations are already shrinking. Moreover, in nations like Switzerland, Spain or Denmark, populations are still growing because of lots of immigrant babies and relative few immigrant deaths.

Average age of population decreased: Immigrants are younger than natives, especially in countries with aging populations like Germany, Italy or Spain. For instance, the average age of people in Spain is 42 years, but the average increases to 43 years if we only consider the native inhabitants, and climbs to 44 if we just count Spanish natives and their children.

Fertility rates significantly increased: Immigrants can add between 0.05 to 0.15 to the total fertility rate (TFR)—the number of children per woman—of a country or region. For instance, in the Spanish province of Catalonia, the TFR was 1.24 children per woman in 2013, but increases to 1.34 if immigrants is included. Newly arrived and Muslim immigrants tend to have much higher fertility. Immigrants from Eastern Europe and Latin America tend to have lower fertility. Based on the numbers released by INE (Spain’s national statistics bureau), Colombian women living in Spain had a 2013 TFR of just 1.0 children, while Spanish women had a TFR of 1.2. On the other hand, Moroccan women living in Spain had a TFR of 3.2 children[1]. They are only 2% of all women of reproductive age in Spain, but they delivered 5% of all babies born in the country.

Overall, foreign immigrants have a very positive demographic impact in Western Europe, as long as these immigrants are properly integrated into their host societies. Needless to say, this is not always easy to do, either economically, politically, or culturally, and it is certainly not cost-free[2].

Immigration can certainly be part of the solution to Europe’s low birth rates, but it cannot be all of the solution. If such immigrants create a false sense of well-being, distracting the native population from the demographic cliff that it is about to go over, it may doom them to destruction.

Because the simple fact is, if Europeans do not start having children, they will commit demographic suicide. It is just a matter of time.

NB. Numbers in this article are mostly data from European official statistical bureaus (like European Union Eurostat, French INSEE, Spanish INE, German Destatis or Swiss Statistical Office), or figures calculated by the author, using such primary data.

The Demographic impact of foreign immigrants on the countries of Western Europe

NB-1: These numbers are an exact addition / subtraction / percentage from original data of the official statistics source, except in a few cases where they are my best estimate (for instance, the UK numbers for children from a mother born abroad are only available for England and Wales).

NB-2: “Foreign mother” is a foreign national living in a European country.

NB-3: “Mother born abroad” is a woman born abroad who is currently living in a European country, who may or may not be naturalized.

NB-4: “Births minus deaths native population” is calculated by deducting, from the country total births minus deaths, the contribution to both from people not born in a particular European country.