Regular contractions, redness, and the descent of the prenatal part of the fetus will occur in the late stage of pregnancy. 1. Regular contractions: the most obvious symptom is the regular pain in the lower abdomen. The pain is caused by contractions, when the pain pregnant women will feel the stomach tight and hard, the pain lasts for a long time, the intervals are short. As labor progresses, the pain will gradually worsen and increase in frequency and duration. 2. Seeing red: 24-48 hours before labor starts, the fetal membranes near the cervical opening separate from the uterine wall and capillaries rupture and bleed, manifesting as a small amount of bloody vaginal discharge, commonly known as seeing red, which is a reliable sign that labor is about to start. 3. Fetal prenatal descent: With the descent of the fetal prenatal part, pregnant women will feel the pressure of the prenatal part on the bladder, and the symptom of frequent urination will appear. Generally speaking, when a pregnant woman experiences regular contractions, it means that labor has started, and she needs to consult a doctor in time and be hospitalized for delivery.