You cannot abort a pregnancy if you cannot see the gestational sac. The conditions for abortion are first to determine intrauterine pregnancy and that the gestational sac is the right size for abortion. There are various ways of abortion, including medication abortion or abortion. If no gestational sac is seen under ultrasonography, it means that only the HCG value is elevated in the laboratory test, but this pregnancy may be the following cases: i. early intrauterine pregnancy; ii. ectopic pregnancy; iii. the gestational age is too small and the pregnant egg is not yet in bed; iv. biochemical pregnancy. The treatment of these different cases is different. Only early intrauterine pregnancy can be aborted, while other cases still need to be reviewed regularly until a clear diagnosis is made.