Some of the most common pregnancy symptoms are a missed menstrual period, implantation bleeding, nausea, cramps, excessive tiredness, fatigue, headaches, backaches, and an increase in the frequency of urination. The majority of these signs could also be related to other medical conditions. In many cases, symptoms of pregnancy do not occur until two or more weeks after conception. Some women report not having any symptoms at all.

Women who experience implantation bleeding often mistake it for their menstrual period. It typically occurs one week after ovulation and may be light pink in color. Unlike a menstrual period, implantation bleeding is usually just a few days of light spotting. Most periods generally last for about a week with a steady flow of dark red blood. Implantation bleeding most often occurs a few days to a week before the monthly menstrual period would be expected.

Cramping of the uterus is one of the most common early pregnancy symptoms. Many women in the early stages of pregnancy fear that the cramps mean something is wrong with the baby, but it is usually just a result of the uterus stretching and contracting to properly accommodate the child growing inside. In a normal pregnancy, this cramping is typically described as mildly uncomfortable rather than painful. Women who experience painful pregnancy cramps are normally advised to consult with a doctor, particularly if they are accompanied by bleeding or spotting.

Not all women experience nausea during the first stages of pregnancy, although it's one of the most common pregnancy symptoms. Nausea usually begins the first five to eight weeks of gestation. "Morning sickness," as pregnancy nausea is often called, can occur at any time of day. Most women only experience nausea during the first trimester, but it is not unheard of for it to last the entire nine months. If the nausea is severe and interferes with a woman's day to day life, a doctor may prescribe prescription medicine to help control it.

Sexually active women who experience pregnancy symptoms can confirm their suspicions by taking a pregnancy test. A home test is typically the fastest, easiest way for a woman to confirm that she is pregnant. Women who test too early may receive a negative result. The most accurate results are received when a woman waits until she misses her period to test, although a positive result is possible at 10 days post-fertilization. Pregnancy can also be confirmed with a blood test as early as 8 days post-fertilization.