In ISRAEL a Ukrainian youngster may earn up to $50,000 — $100,000 annually for her pimp and have nothing left for herself."

There many studies about this, two linked below.

"An estimation of a total number of female sex workers in Ukraine is around 70,000, 15,000 of them are at the 14–19. A study demonstrated that 11% of Ukrainian women who provide sexual services are aged between 12 and 15 years old. In some registered cases the age of Ukrainian girls involved in prostitution was as low as 10 years old.