[1] In 1989, the Soviet Union ranked as the third most populous in the world, above the United States (with 248,709,873 inhabitants according to the 1990 census), although it was well below China and India.

In 1989, about half of the Soviet Union's total population lived in the Russian SFSR, and approximately one-sixth (18%) of them in the Ukrainian SSR.

This post-war increase had contributed to the USSR's partial demographic recovery from the significant population loss that the USSR had suffered during the Great Patriotic War (the Eastern Front of World War II), and before it, during Stalin's Great Purge of 1936–1938.

This significant slowdown may in part be due to the remarkable socio-economic changes that followed the dissolution, that have tended to reduce even more the already decreasing birth rates (which were already showing some signs of decline since the Soviet era, in particular among the people living in the European part of the Soviet Union, beginning from 1988 to 1989).

the population of the 15 former Soviet republics is around 299 million, with much of this growth attributed to the Central Asian states, which have increasing fertility, and in a smaller part Azerbaijan and Russia.