How a child is conceived, that is, the process of conception, begins with the normal reproductive function of both the man and the woman, who generally have intercourse around the time of ovulation, when the sperm provided by the man enters the uterine cavity from the vagina and eventually reaches the fallopian tubes. The sperm can survive in the fallopian tube for 2-3 days and during this time, if it meets the egg provided by the woman, the sperm will contact and fuse with the egg cell membrane and enter the egg to form a fertilized egg. After about 30 hours the fertilized egg starts to move towards the uterine cavity and after 50-72 hours the fertilized egg grows into a mulberry embryo and after 6-7 days the embryo successfully implants into the endometrium and starts to bed. At about 8 weeks, the embryo can vaguely identify the human form, differentiate the tissues of eyes, ears, fingers and toes, and the organs begin to differentiate and develop, and the heart begins to take shape; from the 9th week, the embryo starts to grow and mature; at 16 weeks, the sex of the fetus can be confirmed and some pregnant women begin to feel the fetal movement; at 20 weeks, the fetal movement is obvious; at 24 weeks, the fetus may survive, but the survival rate is very poor and the possibility of premature death is high The viability of the fetus increases gradually after 28 weeks, and the baby is born at full term between 37 and 42 weeks. Preparation for pregnancy is essential for couples preparing to conceive a healthy new life, which usually starts 3 months before conception. During the preparation period the couple needs to go to the hospital and undergo preconception checkups such as routine medical checkups and eugenics screening. In addition, both spouses should quit smoking and limit alcohol, avoid staying up late, and exercise in moderation to improve their immune system. Women should take folic acid supplements in advance to prevent fetal malformations, eat a balanced diet and control their weight. Increasing the frequency of intercourse during ovulation will increase the possibility of pregnancy. If early pregnancy reactions such as menopause, dizziness, chilliness, aversion to oil and grease occur during the preparation period, you can go to the hospital to check blood HCG or urine HCG, ultrasound, etc. to determine whether you are pregnant.