The family was Social Security Institute. In those days there were no pensions. Therefore lost the ability to work the elderly and the disabled had to rely on help from their children and grandchildren. Those who did not have a family, we had to beg for alms. The family was a place of leisure. As a rule, the members of the family relax and have fun together. In the family, that is, marriage, sexual need was met and the need for children. Extramarital affairs were condemned by public opinion. Hide them from others in rural areas or small towns was very difficult, especially if these services were long and regular. The presence of children (in the first place - sons) was a necessary condition in order to qualify as a full-fledged member of society. Childlessness was condemned by public opinion, and married couples without children suffer psychologically from their inferiority. Children also performed and emotional and psychological function, because the parents felt a sense of joy and peace of mind to communicate with them. Thus, for all its shortcomings in traditional families cope with their main functions: they provide themselves economically, socialization of new generations to care for the older generation, and gives birth to as many children as there was enough (even what was then a very high mortality rate) for physical survival of humanity. And the population in different historical periods or growing up, or was relatively stable. Of course, at the time of disasters - wars, crop failures, epidemics, etc. - The population declined dramatically, but eventually the high birth rate compensated for these losses. Under normal conditions, ie, in the absence of such disasters has never been observed steady downward trend in the population because of the excess of deaths over births in a long time - it was only possible in our era. With the onset of industrialization changed dramatically. The family lost their business functions and ceased to be a working collective. Members of the family - husband, wife and grown up children (child labor is particularly true for the period of early capitalism) are beginning to work outside the home. Each of them receives an individual salaries, independent of the composition of the family and its presence at all. Accordingly, there is no need for a sovereign head of the family as the head of family production. In addition, the complexity of the knowledge necessary for socialization and subsequent employment, leads to the extension of the period of study. If the traditional peasant family for 7-year-olds were getting good assistants for the parents, the modern urban family children are learning in school to 17-18 years, and if it comes then in colleges and universities, we remain dependent parents to 22-23 and more years. But even after they start working, they do not give their earnings to their parents and do as soon as possible leave the parental home. Especially enhanced their desire to separate after marriage, and in contrast to the era of primogeniture and minorata when the son inheriting the property remained with his parents, and all the children are separated to prevent this could only housing difficulties (which is very typical for our country). So, in the pre-industrial era played an important role in the economic component needs children. But if he was the only one, the birth rate in our day would have fallen to the ground at all. The economic value of children in modern conditions is expressed even zero, and negative, and no small part. Emotional and psychological component needs in the family and the children is that the family and the children gives a person emotionally satisfying. In the marital relationship is manifested in sexual satisfaction and psychological spheres. Communicating with parents of children brings joy, fills life with meaning. That is why children do not cease to be born, even if they are from an economic point of view, the parents do not bring income, but on the contrary, nothing but losses. Population policy, using only the economic levers (incentives and benefits to families with several children, family tax), never gave strong results. Although quite popular, "the concept of interference in the birth of children" is widespread, including in scientific circles. It prevailing view is that the birth rate is too low because of the difficult material conditions of life. We conclude that it is necessary to alleviate these conditions by providing families with a young child or children, the various benefits and allowances, and the birth rate will increase so that the threat of depopulation is resolved. This view is based only on considerations of everyday logic and "common sense", but is not supported by statistics. Low birth rate, not providing even the replacement rate, observed in all economically prosperous, Western countries. Needless fertility decline occurs not only in the economic crisis, as is the case in today's Russia, but also in the economic recovery. It's been two centuries since then, as demographers became aware of "the paradox of feedback." When the birth rate was very high and its artificial restriction in marriage is not practiced, the average number of children born in families of all social groups do not differ much, and the difference between them was mainly attributable to differences in the average age at first marriage for women belonging to different social groups. The average number of surviving children also depended on social differences in mortality. Reducing child mortality began earlier in the most educated and affluent cultural groups. Therefore, in these groups (earlier than in the other), parents have gained confidence in the fact that their children will survive, and began to practice artificial birth control. Fertility first down at the top of the social, as well as intellectuals, and then - at work, and only in the last turn of the peasants. At a time when society as a whole there is a transition from high to low fertility rates, the mechanism of "feedback" is the most prominent. However, after the decline in the birth rate applies to all social groups, and it does not provide the level of replacement rate, this feedback is weakened and may even disappear. Some authors, resorting to manipulation of data, trying to prove that this feedback is replaced by a straight line, and the rich families have more children on average than the poor. But even with the appearance of such differences in the average number of children among families belonging to different social groups, the differences are small and unprincipled, as none of these groups are no longer able to reproduce itself naturally. In such circumstances, does not matter, in which social groups of the population birth rate is higher, and in which - following, as in all groups, it is still below the replacement rate. In addition to the concept of noise, there is the concept detotsentrizma (French scholar, author A.Landri, and the most active supporter of our country - A.G.Vishnevsky). The child becomes the center of the modern family, which involves one child - this is the concept detotsentrizma. All the same, regardless of the different points of view of demographers, you can recognize one thing - the current family does not think about the death of children. If you used to be a very high probability of dying young children, it is now very few people take into account that the son or daughter will die before their parents. If in countless reports in the media about the accidents necessarily indicate to the victims and family circumstances referred to those episodes when they were the only children of their parents, many families would realize that one child - it's too little. One of the main factors of fertility decline - the destruction of the traditional institution of marriage as a contract in which the husband is obligated to support his family, and his wife have children and keep house. Now, sexual and companionship possible without joint farming, liabilities, etc. Bastards (formally) the children are in many countries of Western Europe from the third to a half of all children born in Russia - nearly 30%. Throughout illegitimate birth rate is growing, but its growth does not compensate for the fall of marital fertility - in general the birth rate is falling. So the problem of the relationship of fertility decline and destruction of marriage is very strong. And here is a direct link between fertility and mortality in our time there. In modern Russian population decline is determined not so much by a high mortality rate as low birth rates. The nature of the replacement of generations depends on the mortality rate only when the level of the latter is high in children and young ages, and a large part of each generation will not live to an average age of parents at the birth of children. In our time, to survive in this age of more than 95% of those born girls. Further reduction in mortality - is extremely important for humanitarian and economic reasons, but has little effect on the nature of the replacement of generations. With a total fertility rate of 1.2-1.3 Child, which is observed in present-day Russia, the population will decline, even if the average life expectancy will reach 80 years of age. Therefore, to increase the birth rate to a level that ensures at least a simple replacement of generations, it is necessary to influence not only on the economic component, but also on the social, emotional and psychological components. Findings It should be emphasized that the birth rate - the most important part of the process of reproduction. The birth rate is measured by various indicators: general factors, age-specific, specific and total fertility rate. The magnitude of the total fertility rate determines the intensity of the process of human reproduction: a simple, restricted or extended replacement of generations occurs in the country. The existence of a regime of low fertility within a generation or two turns a young growing population in the old, the size of which is reduced. Thus, the low birth rate is a major factor in the aging process. The causes of fertility decline are numerous: it is both material and housing, and social, health, etc. The concept of "the needs of children in the family," explains much of the historical transition from high to low fertility.