Hypertrophy is an increase in the size of cells that leads to an overall increase in the size of the tissue or organ. It is a non-cancerous change. Another word for hypertrophy is hypertrophic. In contrast to hyperplasia, hypertrophy does not result in an increased number of cells. Skeletal and cardiac muscle cells commonly undergo hypertrophy in response to increased physical demand and stress on the cells. During pregnancy, the muscle cells in the uterus undergo hypertrophy in response to increased hormone stimulation. Hypertrophy is described as physiologic when it helps or improves the way the organ or tissue functions. Hypertrophy is described as pathologic when it is caused by disease or leads to impaired function.