During which condition does physiological hyperplasia commonly occur?

Physiological hyperplasia is an increase in the number of cells that occurs as a response to a specific stimulus and is considered a normal adaptive mechanism. During pregnancy, hormonal changes, particularly the increase in estrogen, stimulate the growth of breast and uterine tissues to prepare the body for lactation and childbirth. This type of hyperplasia is a fundamental aspect of preparing for physiological changes that support reproduction.

In contrast, malignant tumors are related to pathological changes and can involve uncontrolled cell proliferation rather than a regulated and adaptive response. Chronic inflammation may lead to hyperplasia, but it is typically considered pathological rather than physiological. Injury may result in various cellular responses, but it does not distinctly refer to hyperplasia in the physiological sense. Therefore, pregnancy is the context in which physiological hyperplasia is most prominently recognized, highlighting the body’s natural adaptation to support the developing fetus.