Are you feeling dizzy? Another cause of dizziness – Your uterus can also place pressure on two large vessels, which supply blood to your body: the aorta and the vena cava. When these vessels are compressed under the pressure of your growing uterus, it slows the circulation of blood throughout your body and can cause hypotension. Lay on your side. Typically, you can relieve this symptom by lying on your side, not your back (and it doesn’t matter which side).