It is usually a normal phenomenon to not see a gestational sac with over 1000 human chorionic gonadotropin.
Usually after normal conception, blood HCG increases with the number of days the embryo is pregnant. Generally, HCG in early pregnancy increases regularly at a rate of doubling every two days.
Clinical human chorionic gonadotropin value of 1000, usually indicates the stage of just pregnant or pregnancy time is relatively short, under normal circumstances, blood HCG greater than 2000 theoretical ultrasound to see the gestational sac, so blood HCG1000 ultrasound can not be seen in the uterine cavity in the gestational sac is a normal phenomenon.
It is recommended that the patient go to the hospital one week later for a review, including blood HCG and ultrasound, dynamic monitoring of embryonic development, in order to make an accurate judgment.