Push factors
The most major reason to leave Eastern Europe is there is still severe religious persecution, especially of Jews. Although it is nowhere near as extreme as the Holocaust, there are more anti-semitics and its more common. Another major issue is population decline caused by emigration and falling fertility rate. Emigration leads to loss of money and regression in the economy, which is very clear and common in countries in Eastern Europe. One last major push factor of this region is the conflict between the Ukraine and Russia. The rate of natural increase in Crimea (the disputed land between these two countries) is reducing since many people are fleeing this area to escape the disagreements.
Pull factors
Eastern European countries, for the most part, have rapidly growing economies.They are closing the dwindling gap in difference of GDP per capita between Western Europe. As the economy grows, living conditions will improve, emigration will decrease, and fertility rates will increase. During the process, more jobs will become available to people. In countries like the Czech Republic and Slovakia the GDP per capita is increasing with the growing economies.