Please choose the correct ending to complete the given sentence: Health: [header] How to tell if you're pregnant without a test [title] Pay attention to your menstrual cycle. [step] Pregnant women do not menstruate during the course of their pregnancies. If you miss a period, that is usually the most obvious indicator that you are pregnant.

Ending1: Nonetheless, you can miss periods for other reasons, such as stress or even overexercising. [substeps] If you don't already, get in the habit of keeping track of your menstrual cycle so that you can better detect a late or missed period. Ending2: If you miss at least one or two periods during this time period, you are fertile. [substeps] If you miss two or three periods during the first few days of your menstrual cycle, you may have baby syndrome or another condition that might affect this time period. Ending3: [substeps] Throughout the course of that menstrual cycle, your period begins to decline. Pay attention to a week leading up to it for many women. Ending4: You can receive a menstrual period if you miss several menstrual cycles, according to the center for disease control (cdc). Although you may also need to withhold your periods, women of all ages can get a menstrual period when they are already pregnant.

Answer format: ending1/ending2/ending3/ending4