The most common first signs of pregnancy are a missed period and nausea. A study conducted by the American Pregnancy Association found that 29% of women surveyed reported a missed period as their first pregnancy symptom. Likewise, 25% indicated that nausea was the first sign of pregnancy. There are plenty of other symptoms that many women experience during the early stages of pregnancy. These symptoms include Nausea or morning sickness, tender or swollen breasts, fatigue, or tiredness. While not all women experience these symptoms, if your significant other is showing these signs, it could be a reasonable indication to take a pregnancy test.