Cervical Preparation Before Dilation and Evacuation

The purpose of this research study is to compare three different ways of opening a woman's cervix before her second-trimester surgical abortion. * Osmotic dilators: small rods that, when inserted into the cervix, gently expand to open the cervix * Osmotic dilators plus mifepristone, a medicine that is swallowed * Osmotic dilators plus misoprostol, a medicine that is placed between the cheek and gum Hypotheses: * adding buccal misoprostol 3 hours preoperatively will significantly improve dilation compared to laminaria alone, making procedures faster, easier and safer. * adding oral mifepristone at the time of laminaria placement will confer a similar benefit. * the efficacy of adjunctive misoprostol and mifepristone will be influenced by gestational age, with women later in gestation having increased efficacy from these agents. * significantly more patients who receive adjunctive misoprostol or mifepristone will have adequate initial dilation, fewer will require manual dilation or additional cervical preparation and there will be fewer complications in these arms, although complication rates will be low and we will only be able to detect relatively large differences. * patients will prefer to have the procedure done as quickly as possible with as little discomfort as possible, that cervical ripening with adjunctive misoprostol will be associated with more cramping than osmotic dilators alone and that mifepristone will be well tolerated and may not cause more cramping or other side effects than osmotic dilators alone.