Before scheduling your abortion, it is helpful to know how far along you are. Pregnancy is calculated from the first day of your last menstrual period (not from the day that you think you got pregnant.) This is notated as "LMP." So, while you may be sure that you got pregnant 4 weeks ago, you might be 6 weeks LMP. When you come for your abortion appointment, an ultrasound will determine a more precise gestational age. The price of an abortion and the type of abortion procedure will vary according to LMP.