The reaction of the precursor of child birth, i.e., the reaction before labor, refers to the “aura of labor” in clinical practice, which may appear irregular contractions, the feeling of the fetus descending, and the manifestation of redness, and it is a symptom that often occurs before the delivery to indicate the imminent labor. 1. Irregular contractions: also known as false labor, these are irregular contractions caused by the increased sensitivity of the uterine muscle layer, and most of them are irregular in duration and frequency, which is one of the precursors of labor. 2. Fetal descent: a feeling caused by the descent of the fetal prelude, the descending prelude can press the bladder and cause frequent urination. 3. Redness: it is a small amount of light bloody vaginal discharge, which is a small amount of bleeding caused by the separation of the fetal membranes from the wall of the uterus and the rupture of capillaries, and it often occurs within 24-48 hours before the start of labor.