Influenza A is also known as influenza A (H1N1), with influenza A to rule out whether the fetus is affected, through the symptoms of pregnancy and the various obstetric tests to understand, such as NT examination, Down’s syndrome, four-dimensional ultrasound and other items. Clinical manifestations of influenza A (H1N1) virus infection during pregnancy are similar to those of the general population, with the initial manifestations usually being sudden onset of fever, dry cough, and myalgia, and a temperature of 37.8-40 degrees Celsius at the time of fever, with other symptoms including sore throat, nausea, and headache, etc., and in severe cases there are complications such as respiratory failure and multiple organ insufficiency. With influenza A (H1N1), to exclude whether the fetus will be affected, need to closely observe the clinical symptoms of infection, while close obstetric examination, early pregnancy with influenza is associated with an increased risk of congenital anomalies, including cleft lip, neural tube defects, hydrocephalus and precordial, etc., and associated with pregnancy loss, preterm labor, low birth weight babies, babies less than the gestational age, and stillbirth risk is elevated. If you are infected with influenza A, it is recommended that you take antiviral treatment as soon as possible. Drugs such as oseltamivir are the first medication for antiviral treatment in pregnant women, and should be taken in strict accordance with the doctor’s instructions, rather than at random on your own. If you are infected with influenza A during pregnancy, you should do well in the maternity checkups at all times, such as NT examination, Down’s syndrome screening, 4D ultrasound, to find out whether the fetus has chromosomal abnormality, Down’s syndrome, and developmental deformity of limbs and organs, and if there is any abnormality, you need to do non-invasive, DNA amniocentesis and other tests.