Nausea and vomiting in pregnancy are usually caused by early pregnancy reaction, and it is normal not to hear the fetal heartbeat during early pregnancy reaction. Early pregnancy reaction usually refers to the pregnant woman’s body due to HCG (chorionic gonadotropin) increase and caused by morning sickness, loss of appetite, dizziness and fatigue and other reactions, these are normal physiological phenomena, usually do not need special treatment, in the 12th week of pregnancy disappears on its own. The fetal heartbeat can usually be heard through the fetal heart Doppler instrument after 12 weeks of pregnancy, so when there are early pregnancy reactions such as vomiting, the fetal heartbeat usually can not be heard. If there is any discomfort during pregnancy, it is recommended to go to the Obstetrics and Gynecology Department as soon as possible, under the guidance of the doctor, standardized treatment to ensure the safety of mother and child.