There are fetal heartbeat and buds at 55 days, but the early pregnancy reaction has weakened, considering the normal phenomenon, embryo underdevelopment, etc.. 1. Normal phenomenon: the duration of early pregnancy reaction is different from person to person, some women may be around 4 months early pregnancy reaction weakened or disappeared, but some will last a shorter period of time, may be around 55 days, early pregnancy reaction weakened, and some may not have an early pregnancy reaction or early pregnancy reaction lasts throughout the entire pregnancy, and can not be based on the phenomenon of early pregnancy reaction weakened that the embryo has problems. 2. Embryonic dysplasia: early pregnancy reaction and the body’s hormone levels are elevated, if the embryonic dysplasia occurs in 55 days of pregnancy, it will affect the human chorionic gonadotropin secretion, the body’s other hormone levels will also change, although the test of the fetal heart buds, it may also be embryonic dysplasia. Although there are fetal heart buds on the 55th day, but the early pregnancy reaction is weakened, there may also be other reasons, it is recommended to go to the hospital in a timely manner, improve the examination to clarify the cause of the disease, and under the guidance of the doctor to give targeted treatment or treatment.