['Missing Periods. In most cases, this is the reason women suspect that they are pregnant. ... ', "Spotting. Spotting refers to the phenomenon where bleeding occurs between a woman's menstrual cycle. ... ", 'Vomiting. ... ', 'Feeling Full. ... ', 'Sensitive Breasts. ... ', 'Urination. ... ', 'Pain in the Back. ... ', 'Headaches.']