The most common early signs of pregnancy are tender breasts, fatigue, mood swings and nausea, according to WebMD. A woman's breasts may also feel fuller and swollen.
Fatigue results from the extra progesterone released in a woman's body during early pregnancy, according to WebMD. Naps and an earlier bedtime during the first trimester can help combat this symptom. Energy levels tend to increase during the second trimester. Hormone changes can also cause mood swings, and fatigue and hunger may make a woman's mood swings worse. Nausea and vomiting usually develop around week seven. A small snack before bedtime may improve these symptoms.