The Total Fertility Rate (TFR) in the world has dropped by nearly 50% since 1955, from 5 to 2.5 children per woman, and is forecast to be between 1.8 and 2.2 by 2050.

A UN report states that perhaps for the first time in human history, couples can have a long term relationship without having children. Thanks to birth control methods, and the disconnection between sexuality and reproduction, childbearing in developed countries is the result of a planning decision in at least 50% of the births, and is essentially a decision heavily influenced by women, women and their partners, and more rarely by men.

There are a large number of factors affecting birth rates, and we shall cover the main ones in this note.

Children as caretakers of their parents

In predominantly rural societies, particularly in the absence of retirement plans, children would be caretakers of their parents. As increasingly countries have introduced pension plans, this driver of natality has lost its importance.

The impact of age

Age of the mother is a major factor. Child brides were necessary in early society as the period during which they were fertile was longer and this allowed them to carry aa large number of children. Conversely, women marrying at an older age will not be able to carry many children.

In several developed countries, the average age of women at their first birth is now over thirty. There are several factors that explain this delay: longer studies, the decision of women to have children only once they have well established themselves in life, with a stable job and companion. Women who undertake long periods of study will also delay their first pregnancy and will bear only one child.  Further, the availability of a variety of contraceptive means has nearly eliminated teenage unwanted pregnancies.

Felicity and birth

It has generally been believed that happiness in life has led to women have a larger number of children, in particular if the relationship between partners, and particularly married partners, is a happy one.

Particularly unhappy relationships, such as those leading to depression, are conductive to low fertility if only because anti-depressants reduce libido and fertility.

The cost of parenthood

Some couples take a rational view and consider direct costs and opportunity costs in deciding to have a family. Policies such as ‘speed premium’ – a material encouragement to have a second child in a maximal set period from the birth of the first child – and financial incentives generally, have thus been found to encourage fertility, but only marginally so. In general, monetary aids have not been determinant in increasing fertility rates.

The impact of social infrastructure

As increasingly women have entered the workforce, the task of caring for the children has been passed on to the state.

The availability of material support and social services, such as affordable childcare, flexible working times, or the possibility of parental leave, has a determining effect, particularly for working women with a lower income. Couples who truly want children may move to areas where such services are available.

It appears that the fertility gap is essentially due to the absence of these services.

The impact of education

Education levels of women are also an important factor determining birth rates.

Educated women have more to lose, materially, than less educated women, in financial loss and slower career advancement due to childbirth. They also tend to be more independent and therefore less likely to want to form a family. The values of these women also move to search for quality rather than quantity in their offspring.

Women with higher education are usually older when they have their first child and this, of course, limits the total number of children they will have unless they decide to accelerate their subsequent child-bearing.

Conversely, women with a low level of education seek the financial backing of a husband and are therefore more prone to motherhood.

There is a negative relationship between literacy and birth rates. The most probablyereason is that highly educated women want their offspring to be, in turn, well-educated and that means a more reduced number of children.

Some studies have shown that fertility is associated with the type of employment held by women. Women employed in professions associated with childcare tend to have larger families.

Job stability and the ability of women to exercise their rights and their autonomy is also an important element.

The impact of religion

Religious family have higher birth rates than families that do not practise religious ceremonies.

The domestic division of labor

The domestic division of labor is also a factor influencing fertility.  However, research has led to contradictory results in this respect.

The division of labor does not seem to concern only the split of the domestic tasks, but also whether the woman compounds paid work outside the house with work inside the house, in which case she does not favour having children.

Personal views of mothers on the possible effect of their absence on the development of their children is also an important factor.

The impact of child mortality

The sharp decrease in child mortality is a contributing factor to reduced fertility and opens the way to the demographic transition.

The economic impact

There is a relationship between an increase in GDP and fertility which could be due to increases in public health and nutrition, both of which decrease mortality. In the twentieth century, it is the richest segments of society that reduce the number of children they beget. Social mobility, which allows a decrease in inequalities, is also acquired through a limitation in the number of children.

In the period 1950 to 2007, world GDP per capita increased on average by 2.1%. In that same period, there was a considerable drop in infant mortality, from 140 to 44 per 1000 births and the average life expectancy at birth increased from 43 to 66 years.

It has been suggested that the baby boom of the 1950s was due essentially to the increase in men’s wages, while the decline in child birth of the 1960s was caused by the increase in the wages and income of women. Women tend to have children in periods of unemployment, which would make childbearing countercyclical.

This is known as the substitution effect. It would apply specifically for first births and would depend on the expected duration of the unemployment period and on the level of education of the women since higher educated women tend to have access to more important financial resources allowing them to maintain a certain living standard during their unemployment period unless their husbands are also unemployed.

The general view is that as men’s unemployment reduces the available household income, it reduces the likelihood of men becoming fathers. This is known as the income effect. Women also see the husband as an unlikely father in these conditions.

Traditionally, the cost and burden of raising children was split among the members of a family. However, as families are increasingly nuclear, the parents are the only persons directly involved in raising the family.

An increase in revenue has two contradictory effects. On the one hand, it raises the demand for children while on the other hand it increases the price of the time spent with the children. Either effect can dominate depending on the specific situation.

In developing countries, child labor contributes to the income of the family and therefore additional children represent additional income.

After the crisis of 2009, there was a drop in fertility in 24 European countries, with a time lag. The drop was more pronounced among the immigrant population.

Today, because of the economic recession, the impact of this factor on birth can be again studied and we can indeed see that the birth rates have decreased in most, though not all, European countries. This is particularly true for first births and whatever the age of the parents with the exception of the 40 – 44 age group. On the contrary, the younger the age of the parents, the more sensitive is the impact of the crisis.

Possible explanations include:

  • the fact that it is easier for younger couples to postpone having children
  • younger couples are harder hit by unemployment.

Women over 40, on the other hand, were more reluctant to have a second or third child.

Unemployment of young people forces them to continue to live with their parents and therefore delays the creation of a family.

In Northern Europe, women’s unemployment has led them to have their children earlier, while the reverse has been the case in other European countries, and France in particular.

In conclusion, it is safe to say that uncertainty on the labor market has been found to have a clear negative impact on fertility.

Union instability

Union instability has been deemed to contribute to fertility inasmuch as women want to have children from their new partner after a divorce or separation.

When hit by unemployment, married couples tend to delay family formation, while cohabiting couples adopt an exactly opposite behaviour.

The family norm or social identity

Women are likely to follow the family norm which today, in Europe, is of a family with two children.

There is the possibility that the couple is satisfying the desires of their parents or, alternatively, that one of the members of the couple – the woman – wants to have the reassurance that the other member of the couple attaches value to her decision to become a mother. The desire to have a child takes second role.

There is the desire, by the parents of the fertile woman, to have or not to have a child – in other words, the woman is conceived as a result of a strong desire of her parents, or at least of her mother, to have a child. On the other hand, if the woman or feels this was an accidental act, she may be reluctant to become a mother.

Today’s the social norm is ambiguous. On one hand, women are expected to have children, but when they do so, they lose social value in that they are pushed back into house chores. When their salary is vital for the wellbeing of the family, they have to manage everything and become a superwoman.

The support of the parents is in many cases not available as it used to be a generation ago.

In the countries of Southern Europe there are rigid expectations: women should be married and not work as long as the children are young, 30% of the children are born outside wedlock and TFR is 1.4. This compares with 50% in more liberal societies such as France, Norway and Sweden where TFR is of 1.8 or above. In the latter countries as well, over 80% of the women between 24 and 54 were employed while in the former, the employment rate hovers around 70%.

Today many women in emerging countries use as role models the women they see in soap operas, and these are independent, in full control of their bodies, and none or extremely few have children. The number of hours women watch television has thus become a reliable predictor of the number of children they will have.

Economies of scale

Having two children relatively close to each other creates economies of scale, particularly if they are of the same sex, whether in the fact that clothes and toys can be reused or in that a working woman can take parental leave to take care of  two children simultaneously.


Water pollution has also been found to affect male fertility due to the content in testosterone-blocking chemicals. They reach water through sewage.

Fertilizers, organic solvents and lead modify the functions of sperm. Phthalates are also responsible for diminished sperm counts and testicular damage. Increased temperature, such as that due to long sitting stints, are also responsible for lower sperm count. Stress is also a cause of reduced sperm count.

The loss of independence

Parenthood translates into loss of independence and of control over one’s own life. It also leads to the realization that one’s youth is finished. In today’s society where leisure and games have become easily available, such a commitment may be unwanted.

Family planning

The availability of contraceptives at affordable costs would favors smaller families.

Planned behaviour

According to the theory of planned behaviour (TPB), there are three considerations that lead to the intention of having or not having a child. They are:

  • Behavioural beliefs – i.e. the perceived positive or negative consequences of having a child. They lead to the formation of an attitude towards pregnancy.
  • The perceived expectations and behaviors of important referent individuals or groups and the willingness of the future parents to accept that reaction.
  • Control beliefs – i.e. perceived presence of factors that can influence a person’s ability to have a child.

Gender equity

The theory of gender equity states that the lack of gender equity in social institutions is responsible for very low fertility. Women then have to choose between their roles as mothers and their careers. To allow for higher fertility therefore, countries must allow women to be able to combine work and family.

It implies that employers accept the fact that women, at one stage of their career, may want to work part-time while working full time later on in life when their children have grown. It also implies that social transfers are sufficiently high so that they can replace the resulting decrease in income.


The perception that through procreation, immortality is ensured – or at least continuity of the family line.


Urban fertility is lower than rural fertility and urbanization may well be the most important driver of lower fertility.

Indeed, almost all the factors summarized above are in favor of lower fertility. In the case where urbanization is fed by migration, migrants tend to be individual achievers that are often reluctant to create families.