For many women, the first symptom that they are pregnant is that they miss their period. Every month when you are not pregnant, your uterus sheds its lining so that there is a healthy surface for the embryo to become implanted when you become pregnant. During pregnancy, this monthly cycle stops as the baby and placenta grow in your uterus. This results in the missed period.
Typically you will notice the missed period about two weeks after becoming pregnant. It’s very important to keep track of your last menstrual period because this will help your OB predict when you are ready to deliver. Of course, women can miss periods for a variety of reasons, only one of which is pregnancy. Sometimes travel and stress, not eating enough, or exercising too much can make you miss a period.