Premature Babies

Premature babies can be born due to different medical and lifestyle factors, but in many cases, the exact cause of this childbirth complication can be uncertain. This makes it difficult to prevent or prepare for.

Giving birth to a premature baby does not mean the baby will not grow healthy. A premature baby can grow and develop like normal children through special care. If you are a mother, you can also undergo specific care to reduce anxiety and maintain stability during this period.

Every detail you know about your premature baby helps guide the care they need for a healthy start.

What Defines a Premature Baby?

A premature baby is a term usually given to babies delivered earlier than normal, typically before 37 weeks of pregnancy. Babies with this condition are often referred to as preterm or preemie babies.

Because premature babies arrive before they’ve had the chance to fully grow in the womb, they’re often born with a lower birth weight and may need extra medical care. Being born early can increase the risk of certain health challenges compared to babies who are born full term (after 37 weeks), but many preemies do very well with the right support ⁽²⁾.

Your baby might look a little different from full-term newborns—smaller in size and weight, with a head that appears more noticeable because they haven’t had time to build up body fat. Their skin may look thinner or more see-through, which is completely normal for premature babies.

To determine if a baby is premature, doctors look at how long the baby spent developing in the womb—this is known as gestational age. For instance, if a baby is born at 30 weeks, their gestational age is 30 weeks. This simply means the number of weeks from the first day of the mother’s last menstrual period to the day of birth.

What Causes a Baby to be Born Prematurely?

The causes of preterm birth are often unknown, although there are many known risk factors ⁽²⁹⁾. Here are some more common factors contributing to preterm birth: ⁽¹⁰⁾.

• If you’ve had a baby born early before, you’re more likely to have another premature birth.

• If you’re pregnant with twins, triplets, or more, there’s also a higher chance of delivering early. It’s common for mums expecting multiples to go into labour before 37 weeks.

• Certain conditions affecting your reproductive organs can also raise the risk of preterm birth. For example, a short cervix or early cervical shortening—typically detected through ultrasound in the second trimester—may increase the risk.

• If you’re living with chronic conditions like high blood pressure, diabetes, blood clotting issues, STIs, or if you’re underweight or overweight, these can all play a role in preterm birth. 

• Chronic conditions like high blood pressure, diabetes, blood clotting issues, STIs, or being under- or overweight can increase the risk of preterm birth.

• Pregnancies resulting from in vitro fertilisation (IVF) can also carry a higher risk of prematurity.

• Age is another factor: if you’re under 18 or over 35, there’s a slightly higher chance of giving birth early.

• Lifestyle habits can’t be overlooked, either smoking, drinking, drug use, and high stress levels can all contribute to a higher chance of preterm labour, as can not having regular antenatal care.

• Finally, if you’ve had babies close together, less than six months between pregnancies, that can increase the risk of your baby arriving early.

Other causes of preterm birth include having multiple miscarriages, abortion, and physical injury or trauma. While these are common causes of preterm babies, it is important to bear in mind that anyone can give birth to a preterm baby.

What is the Survival Rate of Preemie Babies?

Thanks to major advances in medical care, even babies born very early now have a chance at survival ⁽¹⁵⁾. In most cases, babies born after 22 weeks of pregnancy may survive with intensive medical support. However, it’s important to understand that this is still considered extremely early, and survival at this stage is rare and challenging.

Babies born between 22 and 26 weeks are known as micro preemies. At this stage, many of their vital organs, such as the brain, lungs, and digestive system, are still developing. This means they’ll need round-the-clock care in a Neonatal Intensive Care Unit (NICU), with support for breathing, feeding, and keeping their bodies warm.

But here’s the hopeful part: with modern technology and skilled medical teams, many micro preemies are now able to survive and grow into healthy toddlers. In fact, studies have shown that a significant number of these tiny fighters go on to have either no or only mild health challenges later in life.

Of course, gestational age isn’t the only factor that matters. A baby’s birth weight, gender (girls often do slightly better), whether they’re a singleton or a twin, and mom’s health during pregnancy can all play a role in how strong their start in life will be. Some babies may also have genetic conditions that affect their outcomes.

While the road for a very premature baby can be tough at first, every extra day in the womb can make a difference. And with loving care and the right medical support, even the tiniest babies can have big futures.

Gestational Age of Preterm Babies and What to Expect

Gestational age is always measured in full weeks ⁽⁹⁾. So, even if your baby was born at 27 weeks and 5 days, their gestational age is still considered 27 weeks until the next full week is reached. Doctors may estimate this age using early ultrasound scans during pregnancy.

Understanding a baby’s gestational age is important because it helps classify how early they were born. Gestational age groups are often categorized based on how far along the pregnancy was at the time of birth, which helps guide the type of care a premature baby may need ⁽⁵⁾.

The World Health Organization highlights the subcategories of preterm babies to be extremely preterm, very preterm, and moderate to late preterm ⁽¹⁷⁾.

Extremely Preterm Babies (Before 28 Weeks)

Extremely preterm babies are born before 28 weeks of pregnancy and are among the most medically fragile newborns. This type of birth occurs in about 2 to 5 out of every 1,000 pregnancies⁽²²⁾.

Because they are born so early, these babies are often significantly underdeveloped and have much lower body measurements compared to full-term infants. On average, an extremely preterm baby may:

• Weigh less than 1,000 grams (approximately 2.2 pounds) ⁽²⁵⁾

• Measure around 13–14 inches (33–35 cm) in length.

• Have a head circumference of about 9–10 inches (23–25 cm)

Every extra week in the womb plays a critical role in a baby’s development, so extremely preterm babies typically face more challenges and need immediate, intensive medical support ⁽²³⁾.

• NICU Stay: These babies require advanced care in the Neonatal Intensive Care Unit (NICU), often for several weeks or months.

• Very Low Birth Weight: Weighing under 1,000g, they appear much smaller and more fragile than full-term babies.

• Smaller Head Size: Head circumference is often below average for their age group.

• Shorter Length: They tend to be significantly shorter at birth.

• Lower Fat-Free Mass: This means they have less muscle and bone weight due to early delivery.

• Higher Waist-to-Height Ratio: Their body proportions may differ slightly as fat and muscle are still developing.

• Vital Support Needed: Most extremely preterm babies need help with breathing, temperature regulation, feeding, and protection from infections.

Though the early days can be difficult, many extremely preterm babies make great progress with proper medical care and family support.

Very Preterm Babies (28 to 32 Weeks)

Babies born between 28 and 32 weeks of pregnancy are considered very preterm ⁽²⁹⁾. While still early, these babies generally have a better chance of survival and fewer complications than those born earlier because they’ve had more time to develop in the womb ^(​​28).

On average, very preterm babies may:

• Weigh between 1,200 and 1,800 grams (about 2.6 to 4 pounds)

• Measure around 14 to 16 inches (35 to 40 cm) in length.

• Have a head circumference of approximately 10 to 11 inches (25 to 28 cm)

Despite this progress, they are still not fully ready for life outside the womb and will need medical care immediately after birth.

• Your baby will likely spend time in a Neonatal Intensive Care Unit (NICU) for specialized support.

• They may weigh less than babies still in the womb at the same gestational age, since most weight gain happens in the final weeks of pregnancy.

• Their lungs may still be developing, so your baby might need help with breathing.

• Preemies may not be ready to suck or swallow on their own and might require feeding through a tube.

• Their bodies may have trouble staying warm, so they’ll be placed in an incubator.

• Continuous care will monitor heart rate, oxygen levels, and overall development.

With the right care and support, many very preterm babies grow and thrive beautifully over time.

Moderate Preterm Babies (32 to <34 Weeks) 

Moderate preterm babies are born between 32 weeks and just under 34 weeks of pregnancy. They are more developed than very or extremely preterm babies and usually face fewer health challenges, but they may still require some medical support after birth ^{(30) (25)}.

On average, moderate preterm babies may:

• Weigh between 1,800 and 2,300 grams (approximately 4 to 5 pounds)

• Measure around 16 to 17 inches (40 to 43 cm) in length.

• Have a head circumference of about 11 to 12 inches (28 to 30 cm)

Here’s what you can typically expect if your baby is born moderately preterm:

• NICU Support (Short-Term). Some moderate preterm babies may need a short stay in the Neonatal Intensive Care Unit for observation.

• Mild Breathing or Feeding Help. Their lungs and sucking reflexes may still be developing, so they might need temporary support.

• Temperature Monitoring. Incubators may be used until your baby can regulate their body temperature.

• Monitoring for Jaundice or Infection. These are more common in preterm babies and will be checked by medical staff.

• Good Outlook. Most moderate preterm babies go home within a few weeks and grow well with routine care.

Late Preterm Babies (34 to 36 Weeks) 

Late preterm babies are born between 34 and 36 weeks of pregnancy. Though they are often close in size and appearance to full-term babies, they are still not fully mature and can have some transitional health needs^{(30) (25)}.

On average, late preterm babies may:

• Weigh between 2,300 and 2,700 grams (around 5 to 6 pounds)

• Measure about 17 to 18 inches (43 to 46 cm) in length.

• Have a head circumference of 12 to 13 inches (30 to 33 cm)

Here’s what you might expect if your baby is born in the late preterm stage:

• Short Hospital Stay. Many late preterm babies don’t need NICU care but may be observed briefly.

• Feeding Challenges. Some may get tired easily while feeding and may need support to gain weight.

• Mild Breathing or Temperature Regulation Issues. These usually resolve quickly with care.

• Increased Monitoring. They’re slightly more at risk for jaundice, low blood sugar, or infection.

• Positive Long-Term Outlook. Most late preterm babies catch up with full-term babies within the first year.

How to Support Your Premature Baby's Development

One of the most powerful ways to support your premature baby’s early development is through a method called Kangaroo Mother Care, recommended by UNICEF and other global health experts. This simple yet effective approach involves holding your baby skin-to-skin, with their chest resting against yours.

For many parents, the time spent apart from their baby in the NICU can feel overwhelming or disconnecting. But skin-to-skin contact helps rebuild that bond—it’s a gentle, reassuring way to feel close again. Beyond emotional connection, this method also has real health benefits. It can help regulate your baby’s body temperature, stabilize their breathing and heart rate, and even support better weight gain and sleep.

Meanwhile, other ways exist to support your premature baby's development ⁽¹³⁾.

Supporting Baby's Vision

One thing you will notice at birth is your baby closing their eyes. This is because they are still adjusting to their new environment. Usually, a baby's vision develops last, so their eyes are often closed. However, when their eyes are opened, they can be easily affected by the brightness of light. To help protect their vision, use hands, a shield, or neat clothes to cover your baby's eyes or the incubator from bright light.

Supporting Baby's Hearing

Premature babies have delicate and developing auditory systems that are especially vulnerable to damage from loud or sudden noises. Excessive noise can cause stress, disrupt sleep, and potentially impact their brain development and overall growth. To help create a calm and safe environment for your baby’s hearing to develop properly, speak softly, use cot covers to muffle loud sounds, and avoid noisy surroundings.

Supporting Baby's Smell

Premature babies have highly sensitive noses that can easily be overwhelmed by strong or harsh scents like perfumes and chemicals. Exposure to these odors, especially in the incubator, can cause discomfort and stress, making it harder for your baby to relax and thrive. To support your baby’s comfort and well-being, avoid using strong perfumes and protect them from harsh smells.

Supporting Baby's Movement and Positioning

Your baby is accustomed to the gentle, confined movements they experienced in the womb. Providing a safe and comforting environment that mimics this feeling is important for their development. You can create a cozy “nest” where your baby can curl up and gently push against, just like in the womb. During care or when your baby becomes unsettled, try to gently contain their arms and/or legs to provide comfort. Positioning your baby’s hands together in the middle or near their face can also encourage a natural, soothing posture that supports their sense of security and well-being.

Touch and Soothing

Babies are always fragile, which means premature babies may be even more fragile. Your baby's skin may be sensitive to touch; therefore, be gentle when touching them and avoid being too firm or tickling. Warm your hands and talk gently before touching to create a better bond. Watch out for your baby's needs and respond to them timely manner.

Communication and Behavior

Babies’ communication involves facial expression, posture, and movement. Grow alongside your baby by learning their language. Follow your baby's behavior closely and make sure to give breaks when needed. 

For premature babies, activities like tummy time can support physical development by strengthening the neck and core muscles. However, it’s essential to adjust tummy time based on your baby’s developmental stage and medical condition. Start with short sessions while your baby is awake and always supervise them closely. If you’re unsure when or how to begin, your healthcare provider or pediatric team can offer personalized guidance.

Regular checkups

Ensure that you take your baby in for regular checkups with your pediatrician or neonatologist. These visits are important for tracking your baby’s growth, including weight gain, development, and overall health. Regular checkups also help catch any concerns early, so your little one can get the right care at the right time.