Final answer:
It's true that a pregnant woman urinates more frequently due to the pressure of the uterus on the bladder and the need to eliminate fetal metabolic wastes. The physiological changes, including an increase in blood volume to handle the requirements of the fetus, further exacerbate this condition.
Step-by-step explanation:
The statement that a pregnant woman urinates more often because the uterus compresses the bladder, and she must also dispose of fetal metabolic wastes is true. During pregnancy, the expanding uterus exerts pressure on the bladder, which reduces its capacity and leads to increased frequency of urination. This issue is compounded by the need to process and eliminate not just the mother's metabolic wastes, but also those produced by the fetus.
In addition, physiological changes occur in the pregnant woman's circulatory system to accommodate the growing fetus. The blood volume increases significantly, by about 30 percent, to manage the demands of fetal nourishment and waste removal. As the uterus grows, it compresses the pelvic blood vessels, sometimes causing varicose veins or hemorrhoids due to impaired venous return from the legs and pelvic region.