Generally, vaginal bleeding is not heavy during a threatened miscarriage, and the abdominal pain is not severe. This typically occurs before the 28th week of pregnancy because the fetal placenta is not yet firmly connected to the mother and its function is unstable, which can easily lead to a threatened miscarriage. During the early stages of pregnancy, it is crucial for pregnant women to be particularly cautious. They should reduce physical activities, avoid vigorous exercise, abstain from sexual activity, and minimize stimulation to the uterus to maintain a cheerful mood. If one experiences unstable emotions, excessive tension, or sadness, it can disrupt normal brain activity, leading to abnormal embryo development and causing a miscarriage.