Can the development of a blastocyst be observed via B-mode ultrasound 36 days after embryo transfer?

Thirty-six days after blastocyst transfer, transvaginal ultrasound examination can clearly visualize the developmental status of the blastocyst. By this time, the embryo has already implanted in the uterus and begun developing, forming a gestational sac. Ultrasound enables clinicians to clearly assess the size and location of the gestational sac, as well as the presence of fetal pole and fetal heartbeat—key indicators of embryonic development. These observations are crucial for evaluating blastocyst viability and ruling out complications such as ectopic pregnancy. Moreover, detection of fetal pole and fetal heartbeat signifies embryonic vitality. Therefore, it is recommended that pregnant women undergo ultrasound examination 36 days after blastocyst transfer to monitor embryonic development and ensure maternal and fetal well-being.