It is possible that no fetal heart and buds are detected at 42 days of pregnancy, but it is important to review the situation. Fetal bud is a stage in the growth and development process of the embryo, which can develop into a human form in the later stage, and fetal heart is the beating of the fetal heart, which can usually be detected in 6-7 weeks, i.e. 42-49 days. If the fetal heart and buds are not detected on the 42nd day of pregnancy, consider that pregnant women usually have irregular menstruation, especially those who are often delayed, and the time of ovulation will be delayed, or the progesterone is low, the conception is late, and the development of the gestational sac is late. At this time, if the pregnant woman has no other discomforts, there is no need to be nervous, and can be rechecked after 1 week, and at the same time, pay attention to the results of the data of progesterone, fasting blood glucose, estradiol, blood HCG, etc., to check for the indicators that may lead to the abnormal development of the embryo. If the fetal heart and buds are still not seen after 60 days, the examination should be repeated in time. If there are no buds and fetal heart after 11 days in the case of a gestational sac with yolk sac, or no buds and fetal heart after 14 days in the case of a gestational sac without yolk sac, then embryonic sterilizations will be considered. The 42 days of pregnancy is still in the early stage of pregnancy, which is more dangerous, and there will also be nausea, vomiting and other early pregnancy reactions. At this time, pregnant women and their families should pay attention to the protection of the safety and health of the pregnant women, suspend the coital activities, but also timely and regular checkups, to check for ectopic pregnancy, uterine fibroids, cysts and other diseases.