In some types of birth control pills, the last week of the pack usually consists of inactive or placebo pills. These pills do not contain any hormones. There are many different types of birth ...

Department of Chemistry, University of Illinois Urbana−Champaign, Urbana, Illinois 61801, United States Beckman Institute for Advanced Science and Technology, University of Illinois Urbana−Champaign, ...

Materials Science and Engineering Program & Walker Department of Mechanical Engineering, The University of Texas at Austin, Austin, Texas 78712, United States ...