The slow growth of fetal buds may be caused by maternal factors or the embryo’s own factors. It is recommended that pregnant women eat on time, eat more fresh vegetables and fruits, supplement folic acid in time, etc. Observe the growth and development of the embryo, if bleeding, abdominal pain and other abnormalities, please consult a doctor in time. First, maternal factors: 1, irregular menstruation: some women have irregular menstruation, delayed ovulation, fertilized egg implantation time is late, the fetal buds will be inconsistent with the week of gestation; however, there are fetal buds, the growth rate of the fetal buds should be normal; 2, insufficient hormone secretion of the mother’s body: human chorionic gonadotropin and progesterone in the early stages of pregnancy can help the embryonic growth and development, if the female ovary luteal secretion of these two hormones When lower, the growth of fetal buds will become slower; 3, the mother suffers from diseases that affect the development of the embryo: such as autoimmune diseases, antiphospholipid syndrome, thyroid dysfunction, etc., which may cause miscarriage, embryonic stagnation, and the fetal buds may grow slowly; 4, other: for example, pregnant women have smoking, drinking, drug abuse, etc., and these unfavorable factors will have a direct impact on the growth and development of the embryo, resulting in the growth of slow growth of the fetal buds. Second, embryonic factors: after the sperm and egg meet, gradually develop in the process, if encountered certain physical and chemical factors of stimulation, may cause chromosomal abnormalities, thus causing embryonic sterilizations.