You can use it to determine your due date, conception date and last menstrual period. The milestone feature is customized to your pregnancy, showing key dates and development stages of your baby's growth. The milestone data can be saved to a text file to be printed, e-mailed or shared.
You can modify "Today's Date" to see how far along you are on any given date. The number of days left are displayed in the Dock for OS X users.