The U.S. Food and Drug Administration issued a public health advisory Tuesday night for the abortion pill mifepristone, better known as RU-486.The agency said in a press release that it is investigating four new reports of death, all in California, following use of RU-486 for medical abortions. All the deaths occurred between September 2003 and June 2005. The advisory follows previous reports of serious bacterial infection, bleeding, ectopic pregnancies that have ruptured, and death; the drug’s black box label warning was subsequently strengthened in 2004.The latest advisory warns of the risk of sepsis or blood infection when having a medical abortion using RU-486. Two of the four deaths involved infection with Clostridium sordelli, a bacteria that can produce fatal toxins in rare cases following childbirth or medical abortions.The FDA action follows an announcement Monday by Danco Laboratories, which markets the drug as Mifeprex, that it was modifying the label to update the safety information.