It is best to have a checkup a week after a spontaneous abortion. This is because most spontaneous abortions clear up on their own, but a small percentage may result in embryonic tissue remaining, so you need to go to the hospital for an ultrasound after a week. If something is found inside the uterine cavity, it will also depend on the size of what is left. If it is relatively small, you can take medication to make it drain out. If it is large, you will need to have the uterus removed. If you have a checkup too early after a spontaneous abortion, there may be tissue in the uterine cavity itself, in which case it may drain out on its own in a few days. If the examination is done too late, when there is residual tissue, it will stick to the uterine wall, making it difficult to remove it during the operation.