The Nebraska statute prohibited "partial birth abortion", which it defined as any abortion in which the physician "partially delivers vaginally a living unborn child before killing the unborn child and completing the delivery." The most common type of abortion performed is suction-aspiration abortion which consists of a vacuum tube inserted into the uterus; others consist of what is known as "D&E" (dilation and evacuation), which is usually used during the second trimester because of the increased size of the fetus. The procedure dilates the cervix, dismembers the fetus, and then removes the body parts with non-vacuum instruments, and, in some cases, uses curettage inside the uterus so that the remaining fetus can be evacuated. Dr. Carhart wanted to use a modified version of this called "D&X" (Dilation and Extraction), which, rather than commencing curettage inside the uterus, extracts part of the fetus first and then begins the process of dismemberment. Carhart stated that he wanted to perform this procedure because he believed it would be safer and would involve fewer risks for the women; it lowered the risk of leaving potentially harmful fetal tissue in the uterus, and it minimized the number of instruments physicians needed to use.