Why can't I see the pregnancy sac?

Pregnancy can not see the gestational sac may be late pregnancy, fetal position is not correct, amniotic fluid turbidity, slow fetal development and other reasons, may also be caused by ectopic pregnancy. Suggestions can be observed for a period of time, after a period of time to go to the hospital to do B-ultrasound examination. If the review is still not visible gestational sac, it is necessary to consider whether to stop the fetus, to do the Qing Dynasty surgery in time.