Maybe you’re wondering when your tummy will finally go from looking like it has a baby inside. Or perhaps you’re plagued by people insisting that you must be having twins (even though you definitely aren’t). Or your belly just doesn’t look quite like the woman next to you in prenatal yoga, even though her due date is only a few days before yours.
It’s normal to have lots of questions about your pregnant belly size. Is it too big? Too small? Too wide? Too high? But the truth is, even though you see that same basketball-under-the-top-look on every maternity clothes model and pregnant movie character, every mom-to-be will show a little bit differently.
Here’s when you might notice your belly start to pop, how you’ll grow throughout your pregnancy and why baby bumps aren’t one-size-fits-all.
When will you start to show during pregnancy?
Eager as you might be to start showing off that bump, it can be hard to pinpoint exactly when your belly will pop. First-time moms often start to show sometime between 16 and 20 weeks, though for others, a bump might not be noticeable until later into the second trimester.
The timeline tends to be earlier for women who’ve been pregnant before — in that case, you may start to see signs of a bump in the first trimester. Again, every mom-to-be and baby bump is different, so if you start showing a little earlier or later, that's normal, too.
What factors can affect the size of your pregnant belly?
Just as no two pregnancies are the same, no two bellies are exactly alike either. The size and shape of your bump can be determined by a variety of factors, including:
- Your frame. If you’re smaller or more petite, your growing belly might be more noticeable earlier on.
- Your core muscles. If your abs were taut before becoming pregnant, your core might hold its shape longer before your belly starts to pop.
- Whether you’ve been pregnant before. On the other hand, most women’s ab muscles tend to be more relaxed after having their first baby. That can mean they tend to show earlier for subsequent pregnancies.
- Your pregnancy weight gain. If you’re gaining more in general, your belly might start to gain extra inches, too. The amount you should gain during pregnancy depends on your starting weight. If you’re concerned that you’re not on track, talk with your doctor.
- Your age. Being in your 20s generally means having stronger core muscles, which means your bump might take longer to emerge.
- Your baby’s position. How a fetus is positioned may also affect how big or small an expectant mother looks.
Why is it so important not to compare pregnant belly sizes?
The fact is, you can't judge a baby by its cover. Whether a woman appears to carry small or large depends less on the bulk of her baby and more on her shape, bone structure and muscle tone. So, while you might not be able to resist checking out other bumps, try not to let someone else’s shape or size affect how you feel about your own belly.
Read This Next
Ignore, too, any comments that tie the size of your belly to the size (or health) of your baby. The only other assessments of a fetus' size that are worth paying attention to are the ones that come from your doctor.
In evaluating how your baby's doing at each prenatal visit, your practitioner will size your baby in utero. This includes measuring your fundal height (a measurement in centimeters from your pubic bone to the top of your uterus) and palpating your abdomen to locate the baby's body parts and estimate your little one's size and position. Other tests, including ultrasounds, may also be used to approximate size.
What might your belly look like in different trimesters?
Everyone’s timeline is a little different, and again, your belly probably won’t look exactly the same as another mom-to-be’s, even if you share the same due date! That said, you can certainly count on your bump becoming rounder and more pronounced as your pregnancy progresses and your baby gets bigger. Here’s what that might look like:
First trimester pregnant belly size
You certainly won’t feel like your pre-pregnancy self during your first trimester. But as far as your belly goes, it will probably look a lot like it did before you got that positive test result. At 3 weeks pregnant, your baby is only the size of a vanilla seed!
But she won’t stay that tiny for long. By the end of your first trimester, at week 13, your baby will have grown to about the size of a lemon — weighing roughly 3 ounces. At this point, many women start to notice that their bellies look a little different, but haven’t quite reached bump territory yet. Instead, your tummy might just stick out a little more than usual, like you ate a really huge meal.
Again, keep in mind that every woman is different, and if you look noticeably pregnant by the end of the first trimester — or still have no sign of a bump — that's normal, too.
Second trimester pregnant belly size
Size-wise, things are probably starting to take off now. (So have the maternity clothes ready!) Even though it’s not yet super prominent, by week 14, you might be able to feel the top of your uterus if you gently press between the top of your pelvic bone and lower abdomen — a sign of the emerging bump to come.
And somewhere around week 20, your enlarging uterus will have swollen enough to push your abdomen forward, likely giving you a little bump. If you normally have an innie belly button, you might notice it starts to pop out around the same time as the rest of your tummy. (It should go back to its old shape — albeit a little stretchier — after you give birth.)
All those changes to the look and shape of your belly are, of course, signs that your baby is growing by leaps and bounds. At week 14 she’s about the size of a navel orange, but by the end of the second trimester at week 27, she’s reached the size of a cabbage and weighs around 2 pounds.
Third trimester pregnant belly size
Your baby puts on a lot of weight during this home stretch as your belly blossoms from big to, well, much bigger! Early on in your third trimester, your tummy will have likely expanded to the point where you can no longer see your legs or feet when you’re standing up.
Between 34 and 35 weeks, your baby will have grown to roughly as big as a 5-pound bag of flour — with your belly expanding all the while. Your cutie’s quarters are definitely getting cramped, and at this point, it might seem like you can’t possibly get any bigger. But chances are, you will! Most babies gain anywhere from 1 to several additional pounds between 35 and 40 weeks.
Can the shape of your pregnant belly predict your baby’s gender?
Has a well-meaning relative (or stranger in the supermarket) insisted they’ve got the inside scoop about your baby’s sex just by looking at your bump? Some people insist that moms of girls have lower, wider bellies while moms of boys have higher, rounder bellies. But it’s just an old wives’ tale.
Ultimately, any gender prediction method has a 50/50 chance of being right. But the only way to know your baby’s sex for certain is through genetic testing — or by waiting until they’re born. If you want to use your growing bump as a playful prediction tool in the meantime, it’s always fun to guess!
Yes 
No 
Trending On What to Expect
