For women who have been confirmed to be in early pregnancy by blood HCG and other tests, the time when the fetal heartbeat and fetal bud are observed by ultrasound needs to be inferred from the ultrasound modality. Abdominal ultrasound is usually around 40 days of pregnancy and vaginal ultrasound is around 35 days of pregnancy.1. Abdominal ultrasound: the earliest time when fetal heart and fetal bud are observed by abdominal ultrasound is 6-7 weeks after menopause. The fetal heart and fetal bud can be observed at 39 days of gestation and can be obviously observed at about 42 days of gestation. 2. Vaginal ultrasound: the fetal heart and fetal bud can be observed earlier at 5-6 weeks of menopause, i.e. at about 35 days of gestation. However, not all pregnant women can have vaginal ultrasound, it needs to be judged according to the specific situation. If a woman usually has regular menstruation, the fetal heartbeat and fetal bud can be observed at 6-7 weeks of pregnancy. If she usually has disrupted menstruation and often has delayed menstruation, ovulation will also be delayed and the time to see the fetal heartbeat and fetal bud will be delayed accordingly, usually around 60 days. If the fetal heartbeat and fetal buds are not seen after 60 days, the pregnancy may be abnormal, such as ectopic pregnancy, spontaneous abortion, biochemical pregnancy, etc., which requires timely medical consultation for clear diagnosis.