Urine odor and color does change during pregnancy. The color of urine varies depending on the mother's level of hydration and whether she ingests vitamins, supplements or beverages such as coffee. Some women report that their urine is clearer than usual during pregnancy, according to Shape magazine.
Second-time mothers use urine odor as an early pregnancy sign, notes Shape. Many women find that early pregnancy changes the smell of their urine. Shortly after a fertilized egg implants into the lining of the uterus, it begins to secrete the human chorionic gonadotropin hormone, better known as hCG. Some women can smell hCG in their urine and find that the urine of early pregnancy has a stronger, more pungent odor than normal.