Women in the first month of pregnancy when the fetus has not yet formed, at this time the fertilized egg has just completed implantation, the volume is relatively small, ultrasound is still difficult to observe. Generally speaking, after 8 weeks of pregnancy, the fetus will take shape, before the formation of the fetus is still in the fertilized egg or follicle, etc., can not be clearly observed by ultrasound the specific situation of the gestational sac, generally through the blood HCG water to determine the normal development of the fetus. It is recommended that women avoid strenuous exercise during the first month of pregnancy to promote better development of the gestational sac. If a woman wants to know the growth status of the fetus after pregnancy, it is recommended that she seeks medical attention in time to clarify whether the fetus has been deposited in the uterus. The morphology of the fetus can be observed through ultrasound after a sufficiently long period of pregnancy. Pregnant women should also be aware of adequate screening for chromosomal disorders during pregnancy in order to promote the health of the fetus.