When I was pregnant with my eldest, by 20 weeks, my belly was enormous. I thought I must be carrying a linebacker. But she was a totally normal size when she was born.
Then I got pregnant with my youngest. My bump at 20 weeks was substantially smaller. She was only one ounce smaller than her sister was when she was born.
So what gives? Can you even tell the size of the baby when looking at a baby bump?
Short answer: No.
And this is why anyone who has ever had babies before you will get an icy glare in their eyes if they ever hear anyone ask with a jocular laugh, “Hey, you got twins or triplets in there?”
The truth is that many other reasons cause your bump to be bigger or smaller. A large baby bump doesn’t automatically mean it’s a boy.
Or that it’s a giant.
And a small one doesn’t mean an undersized baby either. Here’s what you need to know.
- It depends on your own height
If you are tall, which I am not, you most likely have a long abdomen. Not always, mind you. For I do know some tall ladies with short torsos. But if you are tall and have a longer torso, your uterus has more room to grow upwards.
Petite women or women with small torsos have less room in that area, making the uterus push outwards. This results in a bump that looks bigger.
Relevant: Here is how to tell if it is a fat belly or a pregnant belly.
- It’s your first time having a baby
I must remind you that this was not true with my first, but for many women, it is. I think that’s because I ate everything with reckless abandon with my first.
For the first time, women who get pregnant tend to appear smaller in bump size because those ab muscles haven’t been stretched out like pizza dough before. Most women show more bump, and early on too when they have following pregnancies.
And speaking of that, if you have another pregnancy, you may notice those muscles are laxer, or you could be someone that was very fit before pregnancy and continues fitness routines afterward once you’re able to do so. If you’re that person, you may, like me, look smaller in your next pregnancy because your muscles are able to snugly hold the baby bump in better.
- It’s the way the baby is positioned
I think there is just one thing I miss from pregnancy. And that is how my belly changed with each day. I could feel my little cherubs kicking me and moving around. It was such a unique and wonderful feeling.
Your baby is enjoying this time moving around. Of course, the space gets tighter the closer they get to come out of the womb, so the movements get squirmier. As such, your bump can look huge one day and more normal the next, depending on how your baby positions themselves.
- Limited real estate
This goes along with what I was just saying. You have all this stuff in there. Let’s forget for a moment that you’re pregnant…there are a ton of organs in your midsection. As your uterus grows your baby, that uterus begins to take up more space, squishing the other organs.
You know this likely from how much you have to pee. And how often. Something I truly do not miss about pregnancy (in fact, I loved the catheter during and right after my c-section because I did not have to get up to pee 100 times a day).
But it’s not just the uterus. Or the baby in it. It’s the placenta, the cord, the fluid, and then all these other internal organs being shoved out of the way. As such, it can make for a large and unusual baby bump appearance.
- Blame the amniotic fluid
Fun fact: the amniotic fluid in there with your baby can change too. Your doctor will let you know if you have too much or too little, though fluctuations will change by the hour.
At the beginning of your pregnancy, up to 20 weeks, most of that fluid comes from your own bodily fluids. But later on, your baby produces more of it in the form of urine and lung secretions. This means that the amniotic fluid could make your bump look larger or smaller.
But what about the baby’s size?
Look, no one can look at a baby bump and tell you you’re having a big or small baby. I mean, they COULD tell you, but they’re guessing. There is NO way to tell the baby’s size simply by looking at someone’s baby bump.
So, to the balding guy with the big beer gut snickering in line, what’s your excuse?
The size of your baby will be determined mostly by genetics. If you and your spouse are tall, then it stands to reason your baby will inherit those traits.
Likewise, babies tend to come in the same weight range as their parents. You may need to pull out your own baby book and see how much you weighed at birth.
Some other things that make a difference are birth order though it’s not always the case. My eldest was one ounce larger than her little sister, but generally, the following siblings are larger.
Boys tend to be bigger at birth too.
But yeah, you can ignore all those people gawking at your belly and suggesting it’s twins, that you’re the next Octomom or whatever idiotic theory they have to spew forth. Even doctors cannot tell you the size of your baby just by looking at your bump.
And if you want to know how your baby is doing and growing and if all is normal, that ultrasound will help. Just tune out the baby bump banter from everyone else.
Leslie Berry lives with her husband and two young daughters in Los Altos, California, where she loves helping other moms get comfortable with motherhood and embracing the insanity with facts peppered with laughs.
She loves eating too much sushi, exercising, and jamming out on her Fender. Read more about Leslie here.