Embryo development in 30-40 days is the formation of fetal sac, 40-50 days is the formation of fetal bud, 50-60 days of formation of fetal heart, so the general B-ultrasound should be done in about 60 days, then we can see whether the fetal sac, embryo bud and fetal heart rate are normal.
Fetal heart rate is the heartbeat of the fetus, which can be heard in the abdomen with a general stethoscope in 17-20 weeks. Normal fetal heart rate is regular and powerful, like clock tick, 120-160 times / min. if & lt; 120 times / min or & gt; 160 times / min, repeat listening once every 10-20 minutes. If it is not normal, it indicates fetal intrauterine hypoxia. If fetal heart rate is abnormal and accompanied by irregular fetal rhythm, it indicates that fetal hypoxia is more serious.
After the combination of sperm and egg to form a fertilized egg, the implanted fertilized egg slowly splits into a multicellular gestational sac. After more than 30 days of pregnancy, the primordial cells differentiate and gradually form embryo bud, which further develops into fetal heart. This is the process of fetal formation.
Usually the third week of pregnancy to the first month of pregnancy is called the embryonic bud stage, the growth rate of new life in this period is the fastest in its life. At the end of the second week of pregnancy, the sperm and egg that split into cell clusters arrive at the uterus along the fallopian tube about 4 days after fertilization. In the third week, the outer membrane of the cell mass was removed to prepare for implantation. By the fourth week, the blastocyst has been firmly implanted into the uterus. In this period, the prototype of fetal nervous system and blood circulation organs (the basic tissue) has appeared, and the liver has developed obviously since this period; the prototype of eyes and nose has not been generated, but the prototype of mouth and chin can be seen; the umbilical belt connected with the mother also began to develop from this period.
For normal intrauterine pregnancy, general B-ultrasound examination in 6-7 weeks of pregnancy, you can see intrauterine bud and fetal heart tube pulsation. About 50 days after menopause, B-ultrasound examination can see the embryo bud and fetal heart rate. If there is no embryo bud and fetal heart rate, it may be caused by short pregnancy time, which is directly related to the regular menstrual cycle. The pregnant mother can observe for another week to see if the embryo bud and fetal heart rate appear, it is normal intrauterine pregnancy. If the embryo bud and fetal heart rate are still not found, the pregnant mother should consider the possibility of embryo stop development, and should timely go to the hospital to check the situation of the fetus.