20 Things That Happen During Pregnancy That Can Lead To A Big Baby

From the moment a woman sees those two lines appear on the pregnancy test, her life is changed forever. Part of the upheaval to her life is due to the fact that she no longer just has her own health and well-being to think about. As a mom-to-be, she needs to do anything she can to give birth to a healthy and happy baby.

While mom's midwife, doctor, and medical team is first in line to make sure both mom and baby are taken care of, the things that mom does, even before she gets pregnant will have an impact on the overall health of her baby.

Many parents get excited about the thoughts of having a bigger baby, because this often means they sleep through the night faster and there’s less of a worry should baby drop a pound or two the first time they get a cold. While these babies that are born with a little extra weight to snuggle are adorable and able to thrive, there are also risks associated with a baby being born too big.

Babies that are too big can cause health issues that will impact both the mother and the child. Here are 20 pregnancy mistakes that many moms don’t realize can cause a big baby, and some things to keep in mind to help mitigate the risk of having a big baby.

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20 Understanding What A Big Baby Is

Via: People

How can mom monitor her baby’s size if she does not understand what a big baby really is? While there is no hard and fast rule here, babies over 10lbs or 4500 grams are considered bigger than the average. The issue here is when the baby becomes too large to pass safely through mom’s pelvis, which can lead to birth complications, including stalled labor and emergency C-Sections. Although monitoring the size of the baby is not a precise science, your medical team can work on creating a realistic plan for a safe delivery by doing so.

19 Big Baby Last Pregnancy, Guess What?

Via: YouTube

Have you had a big baby in the past? Odds are you are more likely to have another big baby. Mothers who birthed babies who were bigger than eight pounds and 13 ounces (a weight considered to be on the high normal weight for a newborn, are more likely to have a big baby the next time they get pregnant).

This trend increases with each birth as moms often have larger children with every pregnancy. While there is not concrete researched evidence on this tendency, many seasoned healthcare professionals swear by this trend, and who are we to argue?

18 35+ Pregnancy

Via: Oprah

Meaningful careers, education, and meeting our partners later in life have led to the median age for having children increasing. In 1981, 24 percent of Canadian births were to women who were older than 30 years old, by 2011 this number had grown to a whopping 52 percent.

While these moms may be better prepared financially to have their children, there are risks associated with pregnancy after age 35, including a higher risk of miscarriage, and developing complications, including a larger than average sized baby, thanks to an increased risk for gestational diabetes.

17 Skipping On The H20

As the baby presses on mom's bladder, she may be tempted to skip out on drinking that glass of water, but this could be potentially harmful to both her and unborn baby’s health. Water helps our system in terms of clearing out sugar from the kidneys.

Skipping on that glass of water can increase mom’s sugar levels which will, in turn, increase the size of the baby. So if in doubt, reach for the glass of water to help keep things flowing in your kidneys and regulate your sugar levels. A hydrated mom means a hydrated baby.

16 How Was Mom Pre-Pregnancy?

Via: Boldsky

When mom has some extra weight before pregnancy, she also risks the same for her baby, particularly if her Body Mass Index is greater than 30 at the time of conception. Higher weight will increase the chances that mom will develop gestational diabetes in pregnancy, which is linked to bigger babies.

Some doctors advocate for losing as little as five or 10 pounds (or 5% of your body weight) prior to trying to conceive to reduce the risk of these types of complications. Large babies are medically described as having macrosomia, and can face birth complications including their shoulders getting stuck after their head has passed through the birth canal.

15 C-Section Evolution


Technology is impacting our babies. Medical technology and C-sections have created generations of babies who would not have survived in the past. “Philipp Mitteroecker, an anthropologist at the University of Vienna, said women with a particularly narrow pelvis wouldn’t have survived childbirth a century ago.”

This means both women with narrow hips and children with larger heads are more likely to survive and go on to have bigger children, with wider hips of their own. Today in Canada, 27% of births are C-Sections, whereas in the 1950’s and 1960’s only around 10-15% of births were delivered by C-sections.

14 Predicting The Baby's Due Date

Via: Mum's Grapevine

A due date is simply a guide for when the baby is going to arrive. When mom has an irregular cycle or has not kept track of the first date of her last period, errors can occur in terms of predicting the baby’s due date. Technology such as ultrasounds have a margin for error that spans about 1.2 weeks during the first 20 weeks of pregnancy, and as many as two weeks after week 18 of pregnancy. the So baby may be big simply because the due date was not calculated accurately.

13 Taking Concerns Seriously

We are given so much information during our 9 months of pregnancy that it can be hard to know what to prioritize. Remember that your health care professional is working to ensure the safety of both you and your child.

If your doctor is recommending a C-Section birth for your child, do not just dismiss them – they have a good reason, and a planned C-Section will often be easier for mom to recover from when compared to hours of labor followed by an emergency C-Section, which may cause unnecessary stress on both mom and baby’s body.

12 When The Levels Aren't Monitored

Via: Pinterest

Gestational Diabetes is more common than you think. Did you know that seven out of every hundred women will experience it in their pregnancy? If gestational diabetes is ignored, this can cause many other serious conditions in mom and her unborn baby, with a big baby being one of the more minor side effects. As gross as that orange syrupy drink is, that many offices use to test blood sugar levels, it is definitely a worthy sacrifice to make sure that mom’s blood sugar isn’t going to be a danger.

11 Prepare, Prepare, Prepare!


If the baby is big, you may not make your due date. This means your doctor may be recommending something as simple as a labor induction to give the baby a chance to thrive outside of your womb. As disappointing as this may be, remember the safety of mom and the unborn baby should be the number one concern. Prepare yourself to have an honest discussion about the risks associated surrounding proceeding with induction or waiting to make a decision based on what is going to be best for the health of both yourself and the baby.

10 Avoiding Sipping On Milk Or Noshing On Almonds

High calorie food like milk or protein rich almonds, is good for you, and although it’s better for mom and baby than doubling down on Big Macs every day of her pregnancy, it still adds up. While some recent studies have found that children of, “mothers who drank more than five ounces of milk a day during pregnancy were, on average, almost a half-inch taller.

They also had an average of 8% higher blood levels of IGF-1, or insulin-like growth factor, which promotes bone growth” - this is less than one glass of milk each day. Too much is too much, even if it’s healthy food!

9 Genetic Trends

Were you a big baby? What about your partner, parents, or even grandparents? Take the time to look at your own baby book or research whether or not there is a tendency towards bigger babies in your family. Something as simple as the birth weight of a baby can in fact be inherited and is something you should consider when creating your birth plan. And remember, do not be afraid to tell your doctor about this, particularly if there is a strong tendency towards babies who are over 10lbs.

8 Overdue Baby

A few generations ago doctors would let pregnant moms wait for natural labour, sometimes even at 43 or 44 weeks of gestation. Since there is a margin of error for predicting an accurate due date, babies are rarely born on their due date. With that being said, the later a baby is, the more likely they are to be big in size. There are natural ways to encourage an overdue baby to arrive, including eating spicy food, going for a lengthy walk, or engaging in intimate relations.

7 Eating For More Than Two

While pregnant women are eating for two, the calories they need aren’t double the regular amount. As Baby Center reports, “While guidelines vary, the Institute of Medicine says if you're a healthy weight, you need no additional calories in the first trimester, 340 extra calories a day in the second trimester, and about 450 extra calories a day in the third trimester.”

This means eating anything beyond these amounts of calories will make mom pack on the pounds, often leading to a large baby and other related complications during pregnancy and labor.

6 Unreliable Ultrasounds

Via: Pinterest

Technology has come a long way, but ultrasounds aren’t precise at determining the weight of a baby, so keep this in mind. For example, when the baby is believed to be nine pounds, the accuracy on weight for the ultrasound is generally 15 to 20 percent off. So this means the baby could be a full pound lighter or heavier than the ultrasound is predicting. Remember this when making any decisions surrounding baby and birth. Sometimes an extra ultrasound or two are needed to help determine if the baby really is getting too big, too fast.

5 Not Getting Enough Sleep

It can be hard to get a good night's sleep when you are pregnant. Maybe the baby likes to kick non-stop starting at 2AM, or you are too big to get comfortable, but gestational diabetes risks connected with a lack of sleep may have you searching for an afternoon siesta. A recent study has deemed that pregnant women who are not getting enough shut eye are more likely to experience elevated blood sugar levels and gestational diabetes. So reach for that body pillow and practice some self-care. A healthy mom means a healthy baby.

4 Too Much Caffeine

One of the big reasons that doctors recommend mom cut back on caffeine during pregnancy is because of its diuretic effects. In addition to this, caffeine can increase mom’s blood sugar levels and up the chances of her developing gestational diabetes, which can lead to baby getting bigger than usual. It is recommended that pregnant women consume less than 200 mg of caffeine each day until the baby arrives (an eight ounce cup of coffee has about 95 mg of caffeine, whereas decaf has around 2.5 mg).

3 Polycystic Ovarian Syndrome

Polycystic Ovarian Syndrome (PCOS) is a hormonal disorder impacting as many as six to 10 percent of women. In addition to symptoms like growing extra body hair, hair loss, weight gain, oily or acne-prone skin, and trouble getting pregnant, it can also impact a woman’s pregnancy should she conceive. Women with PCOS have greater chances of developing gestational diabetes and having a larger than average sized baby. By focusing on eating healthy calories and remaining physically active during pregnancy, moms-to-be can lessen the chances of these complications.

2 Salt-Filled Foods

Via: Pinterest

Women hear about watching their sugar levels throughout pregnancy all the time, but mom should also be avoiding too much salt in pregnancy. As tempting as those fast food fries may look, consistent consumption of too much salt will increase your blood pressure, and in turn increase the risk of developing preeclampsia.

Daily sodium intake for everyone (pregnant or not) should be no more than 2,400 mg each day, but unfortunately the average American consumes as much as 6,000 to 18,000 mg of salt every day. Too much salt consumption in the third trimester has also been linked to excess fluid retention, so if you’re feeling swollen, skip the salt.

1 Pregnancy With Preeclampsia

Via: Imgrum

No one knows exactly why (yet) but women who develop preeclampsia in pregnancy are also prone to have larger babies. Preeclampsia is a pregnancy condition which should be taken very seriously. It is diagnosed by doctors because of high blood pressure, and includes symptoms like swelling, headaches, blurred vision, and too much protein in the urine. When left untreated preeclampsia can be fatal for both mom and the baby. Preeclampsia impacts around five percent of all pregnancies, and will often lead to mom having to deliver the baby early than normal.

References: National Post, New York Times, Parents, UTSW Med, Mothering, Natural Birth and Baby Care, Fit Pregnancy, Baby Center, and PEW Research.

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