The U.S. Food and Drug Administration approved Plan B emergency contraceptive without a prescription for all women of child-bearing age, officials say. Dr. Janet Woodcock, director of the FDA\'s Center for Drug Evaluation and Research, said the action complied with the April 5 order of the U.S. District Court in New York to make the levonorgestrel-containing emergency contraceptives available as an over-the-counter product without age or other restrictions. Plan B One-Step is an emergency contraceptive intended to reduce the chance of pregnancy following unprotected sexual intercourse or a known or suspected contraceptive failure such as a condom. The primary mechanism of action of levonorgestrel as a progestogen-only emergency contraceptive pill is to prevent fertilization by inhibition of ovulation. A single-dose pill -- 1.5 milligram tablet -- is effective in decreasing the chance of pregnancy and should be taken as soon as possible within three days after unprotected sex, Woodcock said. Plan B One-Step was first approved by the FDA in July 2009 for use without a prescription for women age 17 and older and as a prescription-only option for women younger than age 17, Woodcock said. In April, the product was approved for non-prescription use for women age 15 and older.