The fetal heart and buds are usually not visible on the twenty-fifth day of transfer, but may be detectable at this time if the embryo has settled and is developing quickly. If the embryo is transferred on the third day, twenty-five days after the transfer is equivalent to forty-two days of pregnancy. At this time, the ultrasound may not be able to see the heart of the fetus, but it can be seen whether the embryo is in the uterus or outside the uterus. If the embryo transferred is a blastocyst, the blastocyst is of better quality, it implanted early and develops fast, twenty-five days of transfer is equivalent to forty-five days of pregnancy, and you can usually see the fetal buds and the fetal heart when you have an ultrasound. If pregnant women find that the embryo is outside the uterus during ultrasound examination, it is recommended to consult a doctor in time, under the guidance of the doctor, complete the relevant examinations, clarify the cause of the disease and treat the symptoms.