What Is a Premature Baby? Preterm Birth, Risks and Newborn Care

Created: 16.08.2024 · Last Updated: 17.08.2026 · Category: Obstetrics and Gynaecology · Prepared by the Academic Hospital Web and Editorial Board.

What Is Preterm Birth?

Preterm birth is the birth of a live baby before 37 completed weeks of pregnancy.

The needs and prognosis of a premature baby are not determined by gestational age alone. Birth weight, fetal growth, respiratory status, pregnancy complications and the baby's clinical course after birth are also important.

Not every premature baby requires the same level of intensive care. In general, the earlier a baby is born, the greater the potential need for support with breathing, feeding and temperature control.

What Causes Preterm Birth?

Preterm birth does not have a single cause, and in some pregnancies no definite cause can be identified.

It can occur through:

  • Spontaneous preterm birth: labour starts spontaneously or the membranes rupture early.
  • Medically indicated preterm birth: early delivery is recommended because continuing the pregnancy may present a greater risk to the mother or baby.

Examples of situations that may require medically indicated early delivery include severe pre-eclampsia, some placental disorders and deterioration in fetal condition.

What Are the Risk Factors for Preterm Birth?

  • A previous preterm birth
  • A short cervix
  • Twin or higher-order multiple pregnancy
  • Certain infections during pregnancy
  • Vaginal bleeding during pregnancy
  • Some placental disorders
  • Certain uterine or cervical abnormalities
  • Hypertensive disorders of pregnancy
  • Certain chronic maternal diseases
  • Smoking during pregnancy

A risk factor does not mean that preterm birth will definitely occur, and some women who deliver prematurely have no identifiable risk factor.

What Are the Signs of Preterm Labour?

Symptoms before 37 weeks that may require assessment include:

  • Regular or frequent uterine contractions
  • Pelvic or lower abdominal pressure
  • New or persistent low backache
  • A change in vaginal discharge
  • Vaginal bleeding
  • A gush or persistent leakage of fluid
Regular contractions, vaginal bleeding or suspected rupture of membranes before 37 weeks requires prompt obstetric assessment.

How Is Preterm Birth Classified?

The World Health Organization divides preterm birth into three gestational-age categories:

Classification Gestational Age
Extremely preterm Less than 28 weeks
Very preterm 28 to less than 32 weeks
Moderate to late preterm 32 to less than 37 weeks
A baby born at 32–36 weeks is still physiologically different from a term newborn. Late-preterm babies can still develop respiratory, feeding, temperature-control, glucose and jaundice problems.

What Health Problems Can Premature Babies Develop?

The likelihood and severity of complications generally increase as gestational age decreases.

Possible problems include:

  • Respiratory distress and need for respiratory support
  • Difficulty coordinating sucking, swallowing and breathing
  • Difficulty maintaining body temperature
  • Low blood glucose
  • Increased susceptibility to infection
  • Jaundice
  • Problems involving the brain, eyes, intestines or cardiovascular system in some very premature babies

Being born prematurely does not mean that a child will necessarily develop a long-term disability. Many premature babies grow and develop well with appropriate neonatal care and follow-up.

How Are Premature Babies Cared For?

Care is individualised according to gestational age and clinical condition.

It may include:

  • Thermal care
  • Respiratory support when required
  • Monitoring oxygen levels
  • Monitoring glucose and fluid-electrolyte balance
  • Breast-milk feeding
  • Infection prevention
  • Monitoring growth and development

What Is Kangaroo Mother Care?

Kangaroo mother care is an approach to the care of preterm or low-birth-weight babies based on prolonged skin-to-skin contact with the mother together with breast-milk feeding.

It can help support temperature regulation, breastfeeding and parent-infant bonding and is an important component of modern care for small and premature newborns.

How Are Premature Babies Fed?

Breast milk is an important component of nutrition for premature babies.

Depending on gestational age and feeding ability, breast milk may be given by:

  • Direct breastfeeding
  • Expressed milk given orally
  • A feeding tube

Some very small babies may require appropriate fortification of breast milk to meet increased nutritional requirements.

How Long Do Premature Babies Stay in Hospital?

There is no fixed hospital-stay duration for all premature babies.

Length of stay can depend on:

  • Gestational age at birth
  • Need for respiratory support
  • Ability to feed safely
  • Ability to maintain body temperature
  • Growth and weight gain
  • Episodes of apnoea or bradycardia
  • Infection and other complications

When Can a Premature Baby Go Home?

Discharge is not determined simply by whether the baby no longer requires oxygen or has reached a particular weight or gestational age.

Factors generally considered include:

  • Clinical respiratory and cardiovascular stability
  • Safe and adequate feeding
  • Ability to maintain body temperature
  • Appropriate growth
  • A safe home-care plan
  • Parent education
  • A clear follow-up plan
Premature babies do not necessarily need to remain in hospital until their original due date. Discharge is based primarily on clinical readiness and the ability to continue safe care at home.

What Is Corrected Age?

Corrected age adjusts a premature baby's chronological age for the number of weeks the baby was born early.

For example, a baby born at 32 weeks was approximately eight weeks early. At four months of chronological age, the baby's corrected age would therefore be approximately two months.

Corrected age can be useful when evaluating growth and developmental milestones during infancy.

How Are Premature Babies Followed Up?

Regular follow-up after discharge may include assessment of:

  • Weight, length and head circumference
  • Feeding
  • Motor and neurodevelopmental progress
  • Vision
  • Hearing
  • Vaccination
  • Respiratory health
  • Iron, vitamin and other nutritional requirements

Assess Your Risk of Preterm Birth

If you have a previous history of preterm birth or concerns about preterm labour during pregnancy, appropriate obstetric assessment and follow-up can be planned.

Frequently Asked Questions

What is a premature baby?
A baby born alive before 37 completed weeks of pregnancy is defined as preterm or premature.
What causes preterm birth?
Preterm birth may follow spontaneous preterm labour or early rupture of the membranes. In other pregnancies, early delivery is medically recommended because of concerns for the health of the mother or baby. In some cases, no clear cause is identified.
Before how many weeks is a baby considered premature?
Babies born before 37 completed weeks are preterm. WHO classifies births before 28 weeks as extremely preterm, 28 to less than 32 weeks as very preterm and 32 to less than 37 weeks as moderate to late preterm.
Does every premature baby need neonatal intensive care?
No. The need for neonatal intensive care depends on gestational age, birth weight, breathing, feeding, temperature control and the baby's overall clinical condition.
How long do premature babies stay in hospital?
There is no fixed duration. Gestational age, respiratory support, feeding, temperature control, growth and other medical problems influence the length of hospital stay.
When can a premature baby be discharged?
Discharge is not based solely on reaching a particular weight or gestational age. Clinical stability, adequate feeding, temperature control, appropriate growth, parent preparation and a safe follow-up plan are considered together.
What is kangaroo mother care?
Kangaroo mother care is an approach for premature or low-birth-weight babies based on prolonged skin-to-skin contact with the mother together with breast-milk feeding.
What is corrected age in premature babies?
Corrected age adjusts a baby's chronological age for the number of weeks the baby was born early and can be useful when assessing growth and developmental milestones.
Academic Hospital note: The risk of preterm birth and the care needs of a premature newborn should not be assessed from gestational age alone. Pregnancy history, maternal and fetal health, gestational age, birth weight and the baby's postnatal clinical course should be considered together. You can book an appointment.

References

  1. Academic Hospital. Premature Birth
  2. World Health Organization. Preterm Birth
  3. World Health Organization. Preterm and Low Birth Weight Newborn Health
  4. World Health Organization. Kangaroo Mother Care: A Clinical Practice Guide
  5. American College of Obstetricians and Gynecologists. Preterm Labor and Birth