Pregnancy is counted from the first day of the last menstrual period and is 40 weeks in total. The vast majority of pregnant women give birth around 37-40 weeks of pregnancy, which is considered a full-term labor. The entire pregnancy lasts 40 weeks, and after 37 weeks the fetus is full term. 37-41 weeks is normal, and at this stage the fetus’s organs and systems are well developed. The lungs are also well developed and have a good ability to survive after birth, so the probability of survival is also the highest. However, some pregnant women will have an early onset of labor, which is commonly referred to as preterm labor. 28-37 weeks of labor is considered preterm labor, and babies at this stage of development are not very mature, and the smaller the gestational week, the more poorly developed they are. After birth, the baby needs to be transferred to a neonatal unit, and the probability of the baby surviving depends on the skill level of the local neonatal unit.