Five women who took the abortion pill RU-486 have died from bacterial infections since its U.S. introduction nearly five years ago, the manufacturer reported on Monday."No causal relationship between these events” has been established with the drug, also known as Mifeprex or mifepristone, maker Danco Laboratories LLC said."Childbirth, menstruation and abortion, whether spontaneous, surgical or medical, all create conditions that can result in serious and sometimes fatal infection, and there is no evidence that Mifeprex and misoprostol present a special risk of infection,” the company said in a statement.Misoprostol is a drug that women must take two days after Mifeprex to complete the abortion.Danco said it was sending a letter to alert physicians about the cases and updating warning information on the drug’s label.Mifeprex already carries a warning about the possibility that women who take the drug could experience serious and sometimes fatal infections. The company is updating the label to give physicians more information to help them spot the problem, Danco spokeswoman Cynthia Summers said.