From Wikipedia, the free encyclopedia

Preterm birth
Other namesPremature birth, preemies, premmies
Premature infant with ventilator.jpg
Intubated preterm baby in an incubator
SpecialtyObstetrics, pediatrics
SymptomsBirth of a baby at younger than 37 weeks' gestational age
ComplicationsCerebral palsy, delays in development, hearing problems, sight problems
CausesOften unknown
Risk factorsDiabetes, high blood pressure, being pregnant with more than one baby, obesity or underweight, a number of vaginal infections, celiac disease, tobacco smoking, psychological stress
PreventionProgesterone
TreatmentCorticosteroids, keeping the baby warm through skin to skin contact, supporting breastfeeding, treating infections, supporting breathing
Frequency~15 million a year (12% of deliveries)
Deaths805,800

Preterm birth, also known as premature birth, is the birth of a baby at fewer than 37 weeks' gestational age. These babies are known as preemies or premies. Symptoms of preterm labor include uterine contractions which occur more often than every ten minutes or the leaking of fluid from the vagina. Premature infants are at greater risk for cerebral palsy, delays in development, hearing problems and sight problems. These risks are greater the earlier a baby is born.

The cause of preterm birth is often not known. Risk factors include diabetes, high blood pressure, being pregnant with more than one baby, being either obese or underweight, a number of vaginal infections, tobacco smoking and psychological stress, among others. It is recommended that labor not be medically induced before 39 weeks unless required for other medical reasons. The same recommendation applies to cesarean section. Medical reasons for early delivery include preeclampsia.

In those at risk, the hormone progesterone, if taken during pregnancy, may prevent preterm birth. Evidence does not support the usefulness of bed rest. It is estimated that at least 75% of preterm infants would survive with appropriate treatment, and the survival rate is highest among the infants born the latest. In women who might deliver between 24 and 37 weeks, corticosteroids improve outcomes. A number of medications, including nifedipine, may delay delivery so that a mother can be moved to where more medical care is available and the corticosteroids have a greater chance to work. Once the baby is born, care includes keeping the baby warm through skin to skin contact, supporting breastfeeding, treating infections and supporting breathing.

Preterm birth is the most common cause of death among infants worldwide. About 15 million babies are preterm each year (5% to 18% of all deliveries). Approximately 0.5% of births are extremely early periviable births, and these account for most of the deaths. In many countries, rates of premature births have increased between the 1990s and 2010s. Complications from preterm births resulted in 0.81 million deaths in 2015 down from 1.57 million in 1990. The chance of survival at 22 weeks is about 6%, while at 23 weeks it is 26%, 24 weeks 55% and 25 weeks about 72%. The chances of survival without any long-term difficulties are lower.

Signs and symptoms