Whether or not the fetal heart appears late will be underdeveloped is related to the causes of the late appearance of the fetal heart, generally including physiological factors and pathological factors; physiological factors, such as long menstrual cycle caused by the late appearance of the fetal heart will not affect the development of the fetus. 1. Physiological factors: women’s menstrual cycles have certain individual differences, so the appearance of the fetal heart and buds also have certain differences; if a woman’s menstrual cycle is long, it may lead to the appearance of the fetal heart and buds later, but it will not affect the growth and development of the fetus. 2. Pathological factors: if the fetal heart and buds are observed, and at the same time, the presence of developmental delay is also found, this situation will affect the growth and development of the fetus. Therefore, it is recommended that women need to closely observe the fetal heart and buds in early pregnancy, and if necessary, need to be actively treated.