The love of two sexes begins the great process of conception of life… The fertilized egg travels in the fallopian tube for 4 days to reach the uterine cavity, then stays freely in the uterine cavity for about 3 days, waiting for the uterine lining to be ready, where it finds a suitable place to be buried, which is called implantation. The fertilized egg undergoes several divisions, forms a cell mass, and gradually grows, while it begins to differentiate, with one part becoming a fetus and the other part becoming an accessory organ that supplies the fetus with nutrients and protects it. This is the first week of life Zhang Jing of the Gynecological Endocrine Center of Chengdu Women’s and Children’s Center Hospital In the second week, the little life grows very rapidly, the spine is formed, the brain tissue, the spinal cord and the nervous system, and the eyes, all have a certain shape, and the other end of the spine is a small tail. At this time blood vessels begin to appear, the heart has not yet formed, but there is a heartbeat in the area where the heart is generated. In the fourth week, the heart appears, and in another week, the limbs sprout, the eyes and ears appear, and the lungs and liver begin to take shape. By the seventh week, the fingers and toes begin to appear on the hands and feet, the eyes are clearly visible, the embryo begins to straighten and move in the amniotic fluid, and the whole appearance resembles that of a toddler, and the tail disappears. By the end of the eighth week, the embryo is nearly 3 cm and all the organs have taken their original shape. The following months are just waiting for gradual refinement The little life enters its third month (8-11 weeks) when it starts to be called a fetus. At the beginning of the eighth week, the fetal head accounts for 1/2 of the total length of the fetus, after which growth accelerates and by the end of the twelfth week the body weight increases by one. The internal organ system has begun to function and can swallow amniotic fluid and excrete it as urine. In the ninth week, the vulva of male and female fetuses is approximately similar, and by the end of the twelfth week, it shows the morphology of male and female vulva of mature fetuses. In the fourth month (12-15 weeks), the fetus has reached 16 cm in length and weighs about 120 g. It is growing rapidly. The fetal head is less disproportionate to the body, the legs are relatively longer, and the bones are rapidly ossifying. Under the function of liver, stomach and intestines, green fetal stool has been formed and will be excreted only after birth. Fetal hair appears on the skin. Heart rate is twice as high as that of adults In the fifth month (16-19 weeks), the pregnant woman feels the fetus in her belly kicking itself to show its presence, which is called fetal movement. Another message from the fetus is that the fetal heartbeat can be heard in the abdomen, usually 120-160 beats per minute. The fetus has the ability to hear and can start fetal education. At this time, the fetus is about 25 cm long and weighs 500 grams In the sixth month (20-23 weeks), the fetus is about 30 cm long and weighs 660 grams, with two arms bent over the chest and two knees mentioned on the abdomen. At this time of birth, the fetus often survives for only a few hours, because the respiratory system is not yet well developed In the seventh month (24-27 weeks), the fetus is about 35 cm long, weighs 1000 g, and looks like a little old man. At this time of birth although it can have superficial breathing and crying, it is still difficult to survive The eighth month (28-31 weeks), the fetus is about 40 cm long and weighs about 1700 grams. The fetus moves freely in the uterus, the fetal movements are coordinated, and the position is basically fixed, usually with the head facing downward. The nervous system is further improved, and the lungs and other internal organs have basically completed development. Premature babies born at this time can survive if they are well cared for in a warm box. At the end of the ninth month (32-35 weeks), the fetus is about 45 cm long and its weight can increase by 1000 g in 4 weeks, and its development is basically complete. Premature babies born at this time can have a survival rate of more than 90% if they are well cared for. In the tenth month (36-40 weeks), the fetus is about 50 cm long and weighs 3000 grams. The skin is white with a slight pinkish tinge, there is a white layer of fat on the surface of the body, the breasts are well developed, both breasts are protruding, they burp and suck their thumbs, and the male testicles are often located in the scrotum. Childbirth, although it takes a few hours to a day or a little longer, is a huge ordeal for the fetus to endure. A well-developed fetus is able to withstand oxygen deprivation, compression, etc., and deliver successfully. A child delivered vaginally takes a little longer than a child delivered by cesarean section, but is better able to adapt to the outside world than a child delivered by cesarean section.