If the yolk sac can be seen but there is no germ, it is considered that the menstruation is not normal, the time of conception is too short or the development of the gestational sac has stopped. In most cases, the yolk sac can be seen in the uterus during the 5th-6th week of pregnancy and the germ develops during the 6th-7th week of conception. If the growth of HCG is normal, you can continue to observe. If the HCG growth is normal, you can continue to observe. If you have a repeat ultrasound in a week, and the HCG is low and not doubling every other day but decreasing, it means that the fetus is more likely to stop developing. It is impossible to continue the pregnancy and must be dealt with early.