What is typically the first physical sign of labor?

The first physical sign of labor is commonly recognized as regular contractions. As labor approaches, the body undergoes various physiological changes, but the initiation of contractions signifies the beginning of the labor process. These contractions are rhythmic tightening and subsequent relaxation of the uterine muscles, which help to bring about cervical change and facilitate the delivery of the baby.

While cervical dilation, ruptured membranes, and bloody show are significant indicators of labor progression, they often occur after the contractions have started or as part of the labor process itself. Regular contractions serve as a precursor that prompts further changes in the cervix and ultimately lead to the series of events that follow during labor. Thus, the presence of regular contractions marks the transition into labor more clearly than the other signs.