Due to the different physical conditions of each person, the pregnancy sac may not necessarily be visible on the 38th day of menopause. The exact timing is related to the length and regularity of the pregnant woman’s menstrual cycle, and can be combined with the HCG value to make a judgment if necessary. For pregnant women with regular menstrual cycles of about 28 days, when the ultrasound is performed around 38 days after menopause, in most cases the gestational sac can be seen, and some pregnant women can see the yolk sac inside the gestational sac, but not necessarily the obvious fetal heart and fetal bud. If a pregnant woman has a menstrual cycle of 30 days or more, or if her periods are more irregular, the fertilized egg may be late-setting due to delayed ovulation, so the obvious gestational sac may not be visible at 38 days of menopause, but an obvious cystic dark area may be seen in the uterus. There are also some pregnant women with menstrual cycle of 35 days and above, at 38 days of menopause, the chance of seeing the gestational sac is smaller. You can first judge by HCG value, if the HCG value is high, the possibility of seeing the gestational sac is higher, if the HCG value is low, it is possible that the gestational sac cannot be seen temporarily. If this is the case, the pregnant woman should not worry too much, and she can review the test again after 2 weeks.