It is possible that the ultrasound still does not show early pregnancy after 45 days of menopause because of 2 points: 1) the menstrual cycle itself is long; 2) although the menstrual cycle is 1 month, there is a possibility of lagging ovulation. Every woman has her own fixed menstrual cycle, generally speaking, it is 21-35 days, the average is 28 days, about 35 days after menopause, that is, 1 week after menstruation, ultrasound can see a round or oval gestational sac, 6 weeks of gestation can see the fetal buds and primitive cardiac tube pulsation. However, if the menstrual cycle itself is long, such as 30-40 days, ovulation should be delayed accordingly, then it is very likely that the ultrasound in 45 days after the menopause still does not show early pregnancy, you can use other auxiliary means of detection to determine the pregnancy, such as blood test HCG.