How many weeks does the fetus count as full term?

Pregnant in October, happy and hard. Pregnant mothers count the days every day. When will the fetus be born? At this time, the doctor will tell you that it will be born when it is full term. When is the full-term baby? Term refers to the month when the fetus grows up in the mother. Generally speaking, the fetus will be full-term after staying in the mother's stomach for 37 weeks. The biparietal diameter of full-term fetus should reach more than 9.3 cm. Normal full-term newborns refer to live-born babies born at gestational age of 37-42 weeks (260-293 days), weighing more than 2.5kg and less than or equal to 4.0kg, without any deformity or disease. Full-term babies have obvious facial features, rosy complexion and loud voice, but their thermoregulation ability is poor. At this time, we should pay attention to adding clothes and reducing clothes for the baby! Many pregnant mothers think it is 40 weeks, but it is not. See what the experts say: how many weeks is the full-term fetus?

How many weeks is the fetus full term? Definition of full-term baby: not 40 weeks, but 39 weeks to 40 weeks.

The old definition of full-term baby: the gestational age is 37 weeks to 42 weeks, and all aspects of fetal development meet the production conditions. Now there is a definition of the dislike of full-term babies. Children born less than 37 weeks are called premature babies, those born from 37 weeks to 38 weeks are early babies, those born from 39 weeks to 40 weeks are full-term babies, those born from 4 1 week to 4 1 week are late babies, and those born over 42 weeks are expired babies. So either 40 weeks is a full-term baby, but 39 weeks is a full-term baby.

Generally speaking, full-term infants have the following characteristics:

1. Skin color: ruddy and elastic skin with little fetal hair.

2. Breathing: Full-term babies breathe lightly and quickly, with a frequency of about 40 times per minute, mainly abdominal breathing.

3. Voice: Full-term babies cry loudly and forcefully, especially the first sound after birth.

4. Action: Good swallowing ability, active action and sensitive response. Occasionally sneezing and coughing.

5. Excretion: After the full-term baby is born, it begins to excrete within 12 hours, and the fetus is dark green. After 3 days, the stool color will turn normal.

So as long as the baby has the above performance, it is also a full-term baby! Even if the birth time is not up to standard, it is healthy in all aspects.

What are the characteristics of normal full-term infants? Full-term babies have ruddy skin, full subcutaneous fat and less hair; The head is relatively large, accounting for a quarter of the body; Clear hair, especially hair, with clear stripes; The auricle develops well, and the auricle boat is formed and very straight; Fingernails and toenails are longer than or parallel to fingers; Genital development is good. In addition, full-term infants are born with some primitive reflexes, such as grounding reflex, sucking reflex, grasping response and Moro reflex.

Physiological characteristics of normal term infants and premature infants 1. Respiratory fetal lungs are filled with fluid, and full-term infants are about 30 ~ 35 ml/kg. At birth, about 1/3 of the lung fluid is discharged from the nose and mouth by squeezing the birth canal, and the rest is absorbed by capillaries and lymphatic vessels in the interstitial lung after breathing is established. See Section VIII of this chapter for the generation, properties and functions of pulmonary surfactant. The newborn's breathing frequency is relatively fast, about 40 ~ 60 times/minute. Because it mainly depends on diaphragm movement, it is abdominal breathing.

Premature infants have immature respiratory center, shallow breathing and irregular rhythm, and often have periodic breathing and apnea. The so-called periodic breathing, that is, respiratory arrest: 20 seconds heart rate.

2. The changes of blood circulation after birth are as follows: ① After umbilical cord ligation, the placental-umbilical cord blood circulation is terminated; ② With the establishment of respiration and pulmonary dilatation, pulmonary circulation resistance decreased and pulmonary blood flow increased; ③ The blood volume and pressure of pulmonary vein returning to the left atrium increased obviously, which closed the foramen ovale; ④ Due to the increase of PaO2 _ 2, the arterial catheter was closed after contraction, which completed the transition from fetal circulation to adult circulation. The neonatal heart rate fluctuates greatly, generally 90 ~ 160 beats/min. The mean blood pressure of full-term infants was 70/50 mHg (9.3/6.7 kPa).

Premature infants have high heart rate and low blood pressure, and some of them may be accompanied by arterial catheter opening.

Generally speaking, full-term infants are the healthiest, with stronger immunity than premature infants, early infants, late infants and expired infants, and can adapt to life outside the mother's body more quickly.