Medical progress and discoveries were essential for growth of population. Emphasizing the meaning of hygiene and healthier food improved the peoples well-being. Mortality began to decline, while the number of births stayed high. In 1800 about most of the born children died in the first year, while less than 50% of population reached age over 20 years. By the 1860's European population grew for over 50%, while growth of population in Asia and Africa stagnated.

About 1880 the difference between the number of births and deaths began to decline. Wealthier middle class families began to reduce the births because they wanted to assure their children the education, career and material well-being which would be impossible with larger number of children. Latter began to reduce the number of births also the other social classes what eventually led to balance between the number of births and deaths, while in modern industrial society both births and deaths are on low percentage.