How many weeks is the best for a baby to be born? How many weeks is the best for a baby to be born?

It is generally better for babies to be born at full term. Generally speaking, the baby is full-term at 37 weeks of pregnancy. For the baby, it is best to be born at 40 weeks, because at this time, the baby is relatively mature and it is most appropriate to be born during this period. If the baby is born too prematurely, it may easily lead to fetal maldevelopment. If the baby is born too late, there may also be certain risks!

1. How many weeks is the baby born?

We have always said that pregnancy lasts ten months. This is because under normal circumstances, natural childbirth lasts about 40 weeks, which is exactly ten months if we calculate it as four weeks per month. Therefore, it is healthiest for the baby to be born after 40 weeks in the mother's womb. But this does not mean that babies born before 40 weeks are unhealthy, because as long as the baby is born after nine months and ten days, it is considered full-term, and nine months and ten days is almost 37 weeks.

2. How many weeks is the best for the fetus to be born?

Fetal growth and development at 40 weeks of pregnancy: Most fetuses will be born during this week, but only 5% of babies are actually born exactly on the due date. It is normal to be born two weeks early or two weeks late. However, if there is no sign of labor after two weeks of delay, measures such as induction of labor will be needed to deliver the fetus as soon as possible, otherwise the fetus will be overmature and there will be danger.

At this time, the amniotic fluid environment in which the fetus is located has also changed. The original amniotic fluid was clear and transparent, but now due to the shedding of villi and vernix caseosa on the surface of the fetus' body and the production of other secretions, the amniotic fluid has become a little turbid and milky white. The function of the placenta gradually degenerates from then on until its mission is completed when the fetus is delivered.

3. Characteristics of normal full-term newborns

(I) Appearance characteristics

The baby has less lanugo, a loud cry, rosy skin, clearly separated hair, well-developed auricular cartilage, and a clear scaphoid. The areola is clear, and a nodule of about 3 cm can be felt on the breast; the nails extend beyond the fingertips; the testicles of male babies descend into the scrotum, and the labia majora of female babies completely cover the labia minora, and the sole lines are numerous and crisscrossed. The muscle tone of the limbs is good.

(ii) Body temperature

The body temperature center is not fully developed and has poor regulation ability. Subcutaneous fat is thinner and the body surface area is relatively large, making it easy to dissipate heat. Thermogenesis depends mainly on brown fat. The indoor environmental temperature for newborns should be appropriate. When the room temperature is too high, the blood tends to concentrate through skin evaporation and sweating, resulting in dehydration fever. When the indoor body temperature is too low and heat production is insufficient, neonatal scleredema will occur.

(III) Respiratory system

The fetus does not need lungs to breathe in the uterus, but there are weak respiratory movements. During birth, 1/3 of the lung fluid is squeezed through the birth canal and discharged from the mouth and nose, and the rest is absorbed by the pulmonary interstitial capillaries and lymphatic vessels. If absorption is delayed, wet lungs will occur. After the newborn takes its first breath, it starts crying and the alveoli open. Breathing is shallow and rapid, 40 to 45 times/min. The newborn's chest cavity is small, the intercostal muscles are weak, the chest movement is shallow, and the newborn mainly relies on diaphragm movement, and breathing is abdominal.