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In modern society, young people prefer to stay apart from their parents and live alone in a metropolis. Further, they have a tendency of postponing their parenthood until late 30's or even early 40's.

This trend may involve some factors and the most rooted one can be modern urbanized lifestyle which features high level of mobility and instability of economic situation. In addition, young people facing enormous competition and stress at workplace, have to focus on their jobs and therefor have little time for their families. Obviously under such circumstance, committing to a serious relationship or starting a family, which means tremendous responsibility and dedication, is not a preferable choice. Also the extended family is no longer a realistic option and is replaced by the nuclear one. The cost increase of raising a child is another barrier to late parenthood, and this is especially obvious in major cities around the world.

This change of lifestyle can have some negative effects on individuals and the society as a whole. Firstly low birthrates can result in an ageing population and a lack of labor force in the future. Medical care service will be in high demand and medical cost will rise significantly.

Living alone without long term and stable relationships is widely thought to be associated with personal sense of happiness, which would reduce an individual's general satisfaction with life, but increase the sense of isolation.

Traditionally, cultures and values are passed on in family daily life. However, in modern cities, the young generation living away from the older one have little chance to learn any from their parents. Instead, they are being assimilated by globally popular cultures.