A pregnancy calculator is an alternative and earlier method of determining gestational age and the approximate due date or date of delivery. Ultrasounds done at the right time in pregnancy can quite accurately determine gestational age, albeit with a small margin of error. Pregnancy calculators can be done online from the ease and comfort of your own home and offer an equally reliable method of determining how long you have been pregnant.
However, for you to be able to use pregnancy calculators you need to know the first day of your last menstrual period or LMP. At the beginning of any pregnancy it is not unusual to be confused or uncertain. If you know the first day of your LMP, you ca n say you have been pregnant from that day. Technically, this it means you begin counting pregnancy before you even conceived. Use the pregnancy calculator to help you out with all your pregnancy related dates including fetal age, due date and conception date. Remember that any dates provide by a pregnancy calculator or even doctors are not 100% accurate. It helps to determine the due date of your child right when you find you are pregnant.