Most of the warning signs during week 17 of pregnancy are symptoms of heartburn and dizziness. As your uterus expands and pushes against the abdominal organs, it can cause frequent indigestion symptoms like heartburn, belching, and bad breath. Dizziness is also common and due to your expanding blood vessels. If you feel dizzy, drinking fluids and lying down on your left side may help. Talk to your doctor if you have severe heartburn or dizzy spells that are difficult to manage.