How is premature birth defined?

Written by Zhang Lu
Obstetrics
Updated on May 24, 2025
00:00
00:00

Preterm birth is defined in relation to miscarriage and full-term birth. A birth before 28 weeks of pregnancy is considered a miscarriage; a birth after 37 weeks of pregnancy is considered full-term; and a birth between 28 weeks and 36 weeks and six days is considered preterm. Since preterm birth occurs in the late stages of pregnancy, the fetus has a certain chance of survival. However, efforts should be made to delay the timing of preterm birth as much as possible to increase the survival rate of the fetus. It is generally believed that births between 28 and 34 weeks are considered early preterm, during which the survival probability of the fetus is relatively low; whereas births after 34 weeks up to 36 weeks and six days are considered late preterm, during which the maturity of the fetus is higher and the survival rate is also relatively high.

Other Voices

doctor image
home-news-image
Written by Zhang Lu
Obstetrics
59sec home-news-image

Premature birth is what it means.

Preterm birth refers to giving birth before full-term pregnancy, defined as delivery occurring between 28 and 36 weeks plus 6 days of gestation. Corresponding conditions are miscarriage and full-term delivery: before 28 weeks is termed a miscarriage, while delivery after 37 weeks is termed full-term birth. Because preterm infants already possess certain vital functions, most can survive with appropriate emergency intervention and treatment. However, the risks associated with preterm birth are relatively high and depend on the specific causes of prematurity. Some premature births are due to premature rupture of membranes, while others are medically induced, for example in cases of abruptio placentae or severe preeclampsia. Therefore, it is crucial in clinical practice to provide rational treatment for preterm labor, aiming to extend the duration of pregnancy as much as possible to avoid neonatal death.

doctor image
home-news-image
Written by Zhao Li Li
Obstetrics
47sec home-news-image

Is it normal for a premature baby to weigh more than five jin?

If the newborn is currently premature and weighs a bit over five jin (approximately 2.5 kilograms), it is generally considered within the normal range. Typically, if a newborn weighs more than 2500 grams, it is considered a full-term birth weight and there are no abnormalities. Therefore, if the newborn's weight is within the normal range after birth and there are no abnormalities in the development of the organs, it is possible to observe temporarily without the need for an incubator. It is also crucial to closely monitor the various vital signs of the newborn and pay attention to normal feeding and care.

doctor image
home-news-image
Written by Du Rui Xia
Obstetrics
51sec home-news-image

Is low amniotic fluid likely to lead to premature birth?

During pregnancy, if there is a reduction in amniotic fluid, it is easy for premature delivery to occur. Insufficient amniotic fluid can cause fetal hypoxia in the uterus, which may lead to frequent fetal movements and stimulate uterine contractions, resulting in premature birth. When there is a reduction in amniotic fluid, it is important to replenish it in a timely manner. This can be done by drinking more water, intravenous fluid infusion, or directly injecting saline into the amniotic cavity. To determine the best method to replenish the amniotic fluid, it is advisable to seek treatment under the guidance of a doctor and to closely monitor changes in fetal heart rate and movements.

doctor image
home-news-image
Written by Zhao Li Li
Obstetrics
43sec home-news-image

What is the earliest month that premature birth can occur?

Under normal circumstances, the entire childbirth process for a fetus is divided into three stages: early pregnancy, middle pregnancy, and late pregnancy. Generally, fetal development between 28 to 40 weeks is considered a viable period. During this time, if delivery occurs, the baby's chances of survival are very high. However, normally, a fetus between 37 to 40 weeks is considered full-term, so babies born before 37 weeks are referred to as premature. Premature babies need close monitoring of their developmental status after a normal delivery to avoid potential complications.

doctor image
home-news-image
Written by Zhao Li Li
Obstetrics
41sec home-news-image

Premature birth is how many weeks?

Under normal circumstances, embryos that develop from 28 to 40 weeks are considered viable, and babies born during this period generally have a good survival ability. However, babies born before 37 weeks of amenorrhea are generally considered premature. Therefore, babies born between 28 weeks and 36 weeks plus 6 days are considered premature. Premature babies, due to the immaturity of their organs and systems, are prone to complications. If the baby has already been born, it is recommended to actively pursue appropriate premature care and symptomatic treatment.