Infection is probably the biggest problem.
Infection with Chlamydia is a growing problem among sexually active teens. Bleeding is another problem. About one in ten women bleed so much that they may need a blood transfusion. Despite the best efforts of blood banks there is still a chance of getting HIV or Hepatitis B from a blood transfusion. There have been cases, too, when young women were sent home and literally bled to death in their sleep.