It is not possible to confirm or rule out pregnancy on the basis of one or even several symptoms. Until your doctor detects a fetal heartbeat, any pregnancy symptoms you have experienced are merely indicators that you may be pregnant, says the American Pregnancy Association, or APA. If your uterus seems small but you have reason to think you are pregnant, consult a doctor and request an examination.

One Among Many

A growing uterus is one sign of early pregnancy, but it is by no means the only -- or earliest -- one. Other signs and symptoms include a missed period, breast enlargement, nausea, fatigue, food cravings or aversions and a frequent need to urinate. You may experience a host of symptoms, or only one or two, some of which appear within weeks, or even days, of conception. If you experience symptoms of early pregnancy but don’t see any change in the size of your abdomen, pregnancy is still a possibility. Even if your doctor has conducted a pelvic exam and detects no growth in your uterus, she’s unlikely to rule out pregnancy. She will probably recommend a re-check in several weeks if you fail to get your period and continue to experience pregnancy-like symptoms.

Early Uterine Growth

Situated in the pelvis between your bladder and rectum, the uterus is a pear-shaped organ that typically measures about 3 inches long before pregnancy, according to MedlinePlus, a website of the National Library of Medicine. The primary function of the uterus is to protect and nourish a baby before birth. You’re correct to think that your uterus should be growing if you’re pregnant, because the uterus continually expands to accommodate a developing fetus. You and your doctor may be unable to detect growth in your uterus before 12 weeks, the APA says, because the uterus generally stays tucked among the bones of your pelvis until that point in your pregnancy. As a result, you’re likely to experience many other symptoms of pregnancy before your tummy visibly bulges.

Other Considerations

Numerous reasons could explain why your uterus may appear small, even if it is growing. According to Birth.com, your height, weight and build play a role in how prominent your pregnancy bulge is, as does your baby’s orientation within the uterus. Additionally, if this is your first pregnancy -- or if you have a tight, well-toned body core -- your abdominal muscles and ligaments may be at work keeping your uterus tucked within your pelvis. Family history and ethnicity may also be factors.

Recommendations

While you await confirmation of pregnancy, consider making any lifestyle changes necessary to protect the health of the fetus you may be carrying. Read up on how to protect a fetus from various food dangers, and avoid medical procedures, drug use, exposure to certain chemicals and participation in activities that may be harmful during pregnancy. Schedule a follow-up appointment with your doctor, let her assess whether your uterus has grown and keep her apprised of any new symptoms that develop. If your doctor ultimately rules out pregnancy as the cause of your symptoms, work together to determine the real cause.