Quick take: At 27 weeks pregnant, your baby is about the size of a head of cauliflower — roughly 14.4 inches (36.6 cm) long and weighing around 1.9 pounds (875 grams). Their lungs are maturing, brain activity is surging, and you’ll likely feel frequent kicks and rolls. While not full-term, babies born at 27 weeks have a strong chance of survival with modern neonatal care.
You’re in the third trimester now, and the reality of meeting your baby is getting closer every day. Maybe you’re rubbing your belly absentmindedly while scrolling through baby clothes, or pausing mid-conversation to feel another little jab from inside. One of the most common questions at this stage? “How big is my baby at 27 weeks?” It’s a question that blends curiosity, wonder, and sometimes a touch of anxiety — especially if you’ve seen those viral fruit comparison charts and are trying to picture what’s really going on in there.
Here’s the good news: at 27 weeks, your baby is growing steadily, and their development is nothing short of amazing. They’re not just getting bigger — they’re getting smarter, stronger, and more responsive. In this guide, we’ll walk you through exactly how big your baby is at 27 weeks, what they’re capable of, how their size compares to everyday objects (and even other babies), and what all of this means for your pregnancy journey. No fluff, no vague reassurances — just clear, science-backed answers to the questions you’re actually asking.
Let’s start with the basics: size.
How Big Is a Baby at 27 Weeks Pregnant?
At 27 weeks, your baby is roughly the size of a head of cauliflower. That’s not just a cute comparison — it’s a helpful way to visualize both their length and their growing bulk. On average, a 27-week fetus measures about 14.4 inches (36.6 centimeters) from crown to heel — that’s the length of a standard ruler. In terms of weight, they’re tipping the scales at around 1.9 pounds (875 grams), which is about the same as a large mango or a small loaf of bread.
But here’s the thing: babies grow at different rates, and these numbers are just averages. Some babies at 27 weeks might be a little longer or heavier, while others might be slightly smaller — and that’s usually completely normal. What matters most is that your baby is growing steadily over time, which your provider will track at each prenatal visit.
One mom we spoke with, Sarah, described it like this: “I kept picturing a tiny newborn, but when I saw the cauliflower comparison, it clicked. My baby wasn’t just a little peanut anymore — she was a real, solid little person in there. It made the kicks and rolls feel even more real.”
It’s also worth noting that while length is often measured from head to heel, your provider might use other measurements during an ultrasound, like biparietal diameter (BPD) — the width of your baby’s head — or femur length. These help track growth patterns and ensure everything is progressing as expected.
27 Week Fetal Length and Weight: The Numbers You Need to Know
Here’s a quick breakdown of the averages:
| Measurement | Average at 27 Weeks | Range (Normal Variation) |
|---|---|---|
| Crown-to-Heel Length | 14.4 inches (36.6 cm) | 13.8–15 inches (35–38 cm) |
| Weight | 1.9 pounds (875 grams) | 1.7–2.2 pounds (770–1000 grams) |
| Head Circumference | 9.8 inches (25 cm) | 9.4–10.2 inches (24–26 cm) |
| Abdominal Circumference | 8.8 inches (22.4 cm) | 8.3–9.4 inches (21–24 cm) |
These ranges account for the fact that every baby grows at their own pace. Factors like genetics, maternal nutrition, and even the position of the placenta can influence size. For example, if you or your partner were smaller at birth, your baby might also be on the smaller side — and that’s not necessarily a cause for concern.
During an ultrasound at 27 weeks, your provider will measure several parts of your baby’s body to get a full picture of their growth. These measurements are then plotted on a fetal growth chart, which compares your baby’s size to the average for their gestational age. If your baby is consistently measuring within the normal range, that’s a great sign. If there are any concerns, your provider might recommend additional monitoring or tests.
It’s also worth noting that while weight is important, it’s not the only indicator of health. A baby who is smaller but growing steadily may be healthier than one who is larger but not gaining weight consistently. Your provider will look at the whole picture, including how your baby is moving and developing, to assess their well-being.
What Size Fruit Is a 27 Week Baby?
If you’ve spent any time on pregnancy forums or social media, you’ve probably seen those adorable fruit comparison charts. They’re a fun way to visualize your baby’s size — and at 27 weeks, the comparisons get even more relatable. Here’s how your baby stacks up against some common fruits and vegetables:
- Cauliflower: A whole head of cauliflower is about the same length as your baby at 27 weeks — roughly 14.4 inches. It’s also a great way to picture their growing bulk.
- Mango: A large, ripe mango weighs around 1.9 pounds, which is the average weight of a 27-week baby. It’s also a good visual for their overall size and shape.
- Eggplant: Some charts compare a 27-week baby to an eggplant, which is about 14 inches long. It’s a bit longer than a mango but gives you another way to picture their length.
- Butternut squash: A small butternut squash is another great comparison, as it’s roughly the same length and weight as a 27-week fetus.
These comparisons aren’t just for fun — they can help you and your partner visualize what’s happening inside your belly. One dad we spoke with, Mark, said, “I kept trying to picture what was in there, but it wasn’t until we saw the cauliflower comparison that it really clicked. It made the whole thing feel more real, like we were actually growing a little person.”
Of course, these comparisons are just averages, and your baby might be a little bigger or smaller. What’s most important is that they’re growing steadily and meeting their developmental milestones. If you’re ever unsure about your baby’s size, don’t hesitate to ask your provider — they’re there to help you understand what’s normal and what’s not.
Average Head Circumference at 27 Weeks Pregnancy
At 27 weeks, your baby’s head is growing rapidly — and for good reason. Their brain is developing at an incredible pace, and their head circumference is one of the key measurements your provider will track to ensure everything is on track.
On average, the head circumference of a 27-week fetus is about 9.8 inches (25 centimeters). This measurement is taken around the largest part of your baby’s head, from just above the eyebrows to the back of the skull. It’s an important indicator of brain development, as the skull needs to expand to accommodate the growing brain.
During an ultrasound, your provider will measure your baby’s head circumference and compare it to the average for their gestational age. If your baby’s head is measuring within the normal range (usually between 9.4 and 10.2 inches at 27 weeks), that’s a great sign. If it’s significantly larger or smaller, your provider might recommend additional monitoring or tests to rule out any potential issues.
It’s also worth noting that head circumference can vary based on genetics. If you or your partner have larger or smaller heads, your baby might follow suit — and that’s usually nothing to worry about. What matters most is that your baby’s head is growing steadily over time.
Here’s a quick look at how head circumference changes during the third trimester:
| Gestational Age | Average Head Circumference |
|---|---|
| 26 weeks | 9.4 inches (24 cm) |
| 27 weeks | 9.8 inches (25 cm) |
| 28 weeks | 10.2 inches (26 cm) |
| 29 weeks | 10.6 inches (27 cm) |
As you can see, your baby’s head grows about 0.4 inches (1 cm) every week during this stage of pregnancy. This rapid growth is a sign that their brain is developing as it should, with new neural connections forming every day.
If you’re curious about what’s happening inside your baby’s brain at 27 weeks, here’s a quick rundown:
- Brain activity: Your baby’s brain is now active enough to control some basic functions, like breathing movements and body temperature regulation.
- Sleep cycles: They’re starting to develop regular sleep-wake cycles, which is why you might notice periods of quiet followed by bursts of movement.
- Senses: Their senses are becoming more refined. They can taste the amniotic fluid, hear your voice and other sounds, and even respond to light.
All of this brain development is why head circumference is such an important measurement. If you have any questions about your baby’s head size or brain development, don’t hesitate to ask your provider — they’re there to help you understand what’s normal and what’s not.
Development Milestones at 27 Weeks Gestation
At 27 weeks, your baby is hitting some major developmental milestones. They’re not just growing bigger — they’re growing smarter, stronger, and more responsive. Here’s a look at what’s happening inside your belly right now:
Lung Development
One of the most important milestones at this stage is the development of your baby’s lungs. At 27 weeks, their lungs are starting to produce surfactant, a substance that helps the air sacs in the lungs stay open. This is a critical step toward breathing on their own after birth. While their lungs aren’t fully mature yet, this development means that if your baby were born prematurely at 27 weeks, they’d have a much better chance of survival than they would have just a few weeks earlier.
Brain Activity
Your baby’s brain is growing rapidly, with new neural connections forming every day. At 27 weeks, their brain is active enough to control some basic functions, like breathing movements and body temperature regulation. They’re also starting to develop regular sleep-wake cycles, which is why you might notice periods of quiet followed by bursts of movement.
Senses
Your baby’s senses are becoming more refined. They can taste the amniotic fluid (which changes flavor based on what you eat!), hear your voice and other sounds, and even respond to light. Some studies suggest that babies at this stage can recognize their mother’s voice and may even respond to it with increased movement.
Movement
At 27 weeks, your baby is moving a lot — and you’re probably feeling it! Kicks, rolls, and stretches are all signs that your baby is active and healthy. You might even notice that your baby has a favorite position or time of day for moving. Some moms describe feeling like their baby is doing somersaults or practicing their karate kicks!
Eyes
Your baby’s eyes are also developing rapidly. At 27 weeks, their eyelids are no longer fused shut, and they can open and close their eyes. They might even respond to bright lights by turning away or covering their eyes with their hands.
Fat Storage
Your baby is starting to store more fat, which will help them regulate their body temperature after birth. This fat also gives their skin a smoother, less wrinkled appearance. At 27 weeks, your baby’s skin is still thin and translucent, but it’s starting to fill out as they gain weight.
One mom we spoke with, Lisa, described her baby’s movements at 27 weeks like this: “It’s like she’s practicing for the Olympics in there. I’ll feel a big roll, then a pause, then a series of tiny kicks. It’s amazing to think about all the things she’s learning to do, even before she’s born.”
These milestones are all signs that your baby is developing as they should. If you have any questions about what’s normal at this stage, don’t hesitate to ask your provider — they’re there to help you understand what to expect.
What Can a 27 Week Baby Do in the Womb?
At 27 weeks, your baby is far from just a passive passenger in your belly. They’re active, responsive, and even starting to show some personality. Here’s what your little one is capable of at this stage:
Move with Purpose
Your baby is moving a lot — and not just randomly. At 27 weeks, they’re starting to develop coordinated movements, like stretching, kicking, and even sucking their thumb. Some babies even respond to touch or sound by moving toward or away from the stimulus. If you press gently on your belly, you might feel your baby push back!
Hear and Respond to Sounds
Your baby’s hearing is well-developed by 27 weeks, and they can hear a wide range of sounds, from your voice to music to the dog barking. Some studies suggest that babies at this stage can recognize their mother’s voice and may even respond to it with increased movement. Talking, singing, or playing music for your baby can be a great way to bond with them before they’re born.
Taste What You Eat
The amniotic fluid that surrounds your baby changes flavor based on what you eat. At 27 weeks, your baby can taste these flavors and may even develop preferences for certain foods. Some research suggests that babies who are exposed to a variety of flavors in the womb are more likely to enjoy those foods after birth.
Open and Close Their Eyes
At 27 weeks, your baby’s eyelids are no longer fused shut, and they can open and close their eyes. They might even respond to bright lights by turning away or covering their eyes with their hands. Some babies at this stage start to develop a regular sleep-wake cycle, which is why you might notice periods of quiet followed by bursts of movement.
Practice Breathing
Your baby’s lungs are still developing, but they’re already practicing breathing movements. You might feel these as gentle, rhythmic flutters in your belly. These movements help strengthen the muscles your baby will use to breathe after birth.
Develop a Sleep-Wake Cycle
At 27 weeks, your baby is starting to develop a regular sleep-wake cycle. This means you might notice periods of quiet followed by bursts of movement. Some moms describe feeling like their baby is more active at certain times of day, like in the evening or after a meal.
One dad we spoke with, James, said, “It’s wild to think about all the things our baby is learning to do in there. We talk to her every night, and sometimes she’ll kick or roll right after we do. It’s like she’s saying, ‘I hear you!’”
These abilities are all signs that your baby is developing as they should. If you have any questions about what’s normal at this stage, don’t hesitate to ask your provider — they’re there to help you understand what to expect.
Is 27 Weeks Considered Full Term Baby Size?
At 27 weeks, your baby is growing rapidly, but they’re not yet considered full-term. Full-term pregnancy is defined as 39 to 40 weeks, and babies born before 37 weeks are considered preterm. While a 27-week baby is much larger and more developed than they were just a few weeks ago, they still have a lot of growing and maturing to do before they’re ready for life outside the womb.
Here’s a quick look at how a 27-week baby compares to a full-term baby:
| Measurement | 27 Weeks | Full-Term (40 Weeks) |
|---|---|---|
| Length | 14.4 inches (36.6 cm) | 19–21 inches (48–53 cm) |
| Weight | 1.9 pounds (875 grams) | 6.5–9 pounds (2.9–4 kg) |
| Head Circumference | 9.8 inches (25 cm) | 13–14 inches (33–35 cm) |
| Lung Maturity | Starting to produce surfactant | Fully mature |
| Fat Storage | Starting to store fat | Well-developed fat stores |
As you can see, there’s still a lot of growth and development that needs to happen between 27 weeks and full-term. Babies born at 27 weeks are considered very preterm and may face some challenges, such as breathing difficulties, feeding issues, and a higher risk of infections. However, with modern neonatal care, the survival rate for babies born at 27 weeks is quite high — around 90% or more, according to the American College of Obstetricians and Gynecologists (ACOG).
That said, every week counts when it comes to preterm birth. Babies born at 27 weeks are more likely to experience complications than those born at 32 weeks or later. This is why providers work hard to prevent preterm labor and give babies as much time as possible to grow and develop in the womb.
If you’re at risk for preterm labor, your provider might recommend treatments like progesterone supplements or cervical cerclage (a stitch in the cervix) to help prolong your pregnancy. They might also suggest lifestyle changes, like avoiding strenuous activity or managing stress, to reduce your risk.
One mom we spoke with, Maria, shared her experience with preterm labor at 27 weeks: “I was terrified when I went into labor so early, but the NICU team was incredible. They explained everything, answered all my questions, and gave me hope. My baby spent 10 weeks in the NICU, but today she’s a healthy, happy toddler. Every week in the womb makes a difference.”
If you’re ever worried about preterm labor or your baby’s size, don’t hesitate to talk to your provider. They’re there to help you understand your risks and options, and to support you through every stage of your pregnancy.
How Much Does a 27 Week Baby Weigh Compared to a Watermelon?
At 27 weeks, your baby weighs about 1.9 pounds (875 grams) — which is roughly the same as a small watermelon. But let’s break that down a little further, because comparing a baby to a watermelon can be a bit confusing. After all, a watermelon can vary a lot in size, from a tiny personal one to a giant picnic variety!
Here’s a more precise comparison:
- A small seedless watermelon (about 5–6 inches in diameter) weighs around 2 pounds — just a little heavier than your 27-week baby.
- A large slice of watermelon (about 1/8 of a medium watermelon) weighs roughly 1.5–2 pounds, which is close to your baby’s weight.
- A personal-sized watermelon (about 10–12 inches long) weighs around 4–5 pounds, which is closer to the weight of a baby at 32–34 weeks.
So while your baby isn’t quite as heavy as a whole watermelon, they’re definitely in the same ballpark as a small one or a large slice. It’s a fun way to visualize their size, especially if you’re trying to picture how much they’ve grown since the first trimester.
Of course, these comparisons are just averages, and your baby might be a little bigger or smaller. What’s most important is that they’re growing steadily and meeting their developmental milestones. If you’re ever unsure about your baby’s size, don’t hesitate to ask your provider — they can give you a clearer picture based on your ultrasound measurements.
It’s also worth noting that while weight is an important indicator of growth, it’s not the only one. Your provider will look at a variety of measurements, including length, head circumference, and abdominal circumference, to get a full picture of how your baby is developing. They’ll also consider how your baby is moving and whether they’re hitting their developmental milestones.
One mom we spoke with, Priya, said, “I kept trying to picture my baby’s size, but it wasn’t until I saw the watermelon comparison that it really clicked. It’s wild to think that something so small is already so strong and active. Every kick feels like a little reminder of how much they’re growing.”
27 Weeks Pregnant Baby Size Compared to 28 Weeks
At 27 weeks, your baby is growing rapidly — but how do they compare to just one week later, at 28 weeks? The differences might seem small, but every week counts when it comes to fetal development. Here’s a side-by-side look at how your baby’s size changes between 27 and 28 weeks:
| Measurement | 27 Weeks | 28 Weeks |
|---|---|---|
| Length (Crown-to-Heel) | 14.4 inches (36.6 cm) | 14.8 inches (37.6 cm) |
| Weight | 1.9 pounds (875 grams) | 2.2 pounds (1000 grams) |
| Head Circumference | 9.8 inches (25 cm) | 10.2 inches (26 cm) |
| Abdominal Circumference | 8.8 inches (22.4 cm) | 9.1 inches (23.1 cm) |
As you can see, your baby grows about 0.4 inches (1 cm) in length and gains roughly 0.3 pounds (125 grams) in weight between 27 and 28 weeks. Their head circumference also increases by about 0.4 inches (1 cm), reflecting the rapid brain development happening at this stage.
While these differences might seem small, they add up quickly. By 28 weeks, your baby is starting to look more like a newborn, with smoother skin, more fat stores, and even more defined features. Their lungs are also continuing to mature, and they’re becoming more responsive to sounds and light.
One mom we spoke with, Emma, described the difference between 27 and 28 weeks like this: “At 27 weeks, I felt like my baby was active but still had a lot of room to move. By 28 weeks, it was like they’d grown overnight — the kicks were stronger, and I could feel them pressing against my ribs. It was a little uncomfortable, but also amazing to think about how much they’d grown in just a week.”
It’s also worth noting that while these averages are helpful, every baby grows at their own pace. Some babies might grow more quickly between 27 and 28 weeks, while others might grow more slowly. What matters most is that your baby is growing steadily over time, which your provider will track at each prenatal visit.
If you’re curious about how your baby’s size compares to the averages, don’t hesitate to ask your provider. They can give you a clearer picture based on your ultrasound measurements and help you understand what’s normal for your baby.
Growth Chart: 27 Weeks Fetal Size
If you’re a numbers person, you might be curious about how your baby’s size compares to the averages for their gestational age. A fetal growth chart is a helpful tool that plots your baby’s measurements against the typical range for their age. Here’s what a growth chart for a 27-week fetus might look like:
| Measurement | 5th Percentile | 50th Percentile (Average) | 95th Percentile |
|---|---|---|---|
| Length (Crown-to-Heel) | 13.8 inches (35 cm) | 14.4 inches (36.6 cm) | 15 inches (38 cm) |
| Weight | 1.7 pounds (770 grams) | 1.9 pounds (875 grams) | 2.2 pounds (1000 grams) |
| Head Circumference | 9.4 inches (24 cm) | 9.8 inches (25 cm) | 10.2 inches (26 cm) |
| Abdominal Circumference | 8.3 inches (21 cm) | 8.8 inches (22.4 cm) | 9.4 inches (24 cm) |
This chart shows the range of normal measurements for a 27-week fetus. The 50th percentile represents the average size, while the 5th and 95th percentiles represent the lower and upper ends of the normal range. If your baby’s measurements fall within this range, that’s a great sign. If they’re significantly smaller or larger, your provider might recommend additional monitoring or tests.
It’s important to remember that growth charts are just one tool your provider uses to assess your baby’s health. They’ll also consider how your baby is moving, whether they’re hitting their developmental milestones, and how their size compares to their own growth pattern over time. A baby who is consistently measuring in the 10th percentile, for example, might be perfectly healthy if they’ve always been on the smaller side.
One mom we spoke with, Rachel, said, “I was a little worried when my baby measured in the 15th percentile at 27 weeks, but my provider explained that it was still within the normal range. She also pointed out that my baby had grown steadily since my last ultrasound, which was a great sign. It helped me relax and focus on the bigger picture.”
If you have any questions about your baby’s growth chart or measurements, don’t hesitate to ask your provider. They can help you understand what’s normal and what’s not, and give you peace of mind as your pregnancy progresses.
What Is the Average Size of a 27 Week Baby in Inches?
At 27 weeks, the average size of a baby is about 14.4 inches (36.6 centimeters) from crown to heel. This measurement is taken from the top of your baby’s head to the bottom of their heels, and it’s one of the key indicators your provider will use to track their growth.
Here’s a breakdown of what that length looks like in everyday terms:
- A standard ruler is 12 inches long, so your baby is about 2.4 inches longer than that.
- A large sub sandwich is roughly 12–14 inches long, so your baby is about the same length as a footlong sub.
- A head of cauliflower is also about 14.4 inches long, which is why it’s such a popular comparison for a 27-week baby.
It’s also worth noting that while crown-to-heel length is the most common way to measure fetal size, your provider might use other measurements during an ultrasound, like crown-to-rump length (from the top of the head to the bottom of the buttocks) or femur length (the length of the thigh bone). These measurements help track growth patterns and ensure everything is progressing as expected.
One mom we spoke with, Jessica, described her baby’s length at 27 weeks like this: “I kept trying to picture how big my baby was, but it wasn’t until I saw the ruler comparison that it really clicked. It’s wild to think that something so small is already so long — and growing every day!”
