When do your stomach start getting hard

Braxton-Hicks contractions are named after Dr. John Braxton Hicks, an obstetrician from England who practiced in the mid- to late 1800s. Braxton Hicks observed that, "after many years’ constant observation, I have ascertained it to be a fact that the uterus possesses the power and habit of spontaneously contracting and relaxing from a very early period of pregnancy."

Braxton-Hicks Contractions: What You Need to Know

What: Practice/warm up contractions that do not cause or signal labor, or dilate the cervix

When: Second or third trimester; usually felt/noticed earlier in the second trimester for subsequent pregnancies

Where: Usually in the upper to mid abdomen, in the front of your mid-section

Why: While we don't know for certain the cause or purpose of Braxton-Hicks, it is believed to be a way to help prepare the uterus for eventual labor and birth. In basic terms, the uterus is a muscle and muscles can contract when irritated. 

Who: People who are pregnant, though not everyone will experience Braxton-Hicks contractions during pregnancy

How: Braxton-Hicks contractions are usually felt as a tightening and a hardening of the abdomen (the uterus). They usually last only 20-30 seconds and may happen throughout the day without a regular pattern. They may cause discomfort or feel difficult to move or bend over during. 

What Triggers Braxton-Hicks Contractions?

When you pay attention to Braxton-Hicks contractions long enough, you will likely begin to notice that they are routinely triggered by certain activities, including:

• Movement after being still, or exercise
• A full bladder, or after emptying your full bladder when you pee
• Orgasm or various sexual acts
• When your baby is moving around a lot 
• If you are dehydrated
• If your belly has been touched, bumped, or manipulated in some way
• "Overdoing it" -- too much activity throughout the day

What Can You Do About Braxton-Hicks Contractions?

The short answer is: nothing. Even if it was possible to remove all of the triggers listed above, you would likely still have them. The good news is that BH contractions are generally short -- they're over before you know it and you're not out too much time or energy. If you have a Braxton-Hicks contraction that feels particularly uncomfortable or are having them frequently, you can try a few remedies to alleviate them, including:

• Drink water to rehydrate
• Take a warm bath
• Rest -- lay down, sit down 
• De-stress in a way that works best for you

When Should You Be Concerned About Braxton-Hicks Contractions?

The headline above is misleading -- Braxton-Hicks contractions are not concerning. It's when a Braxton-Hicks contraction is not a Braxton-Hicks contraction that causes concern or a change in what is happening. If you have contractions that come with any of the following signs, contact your OB, midwife, or doctor, as these signs may signal the beginning of labor:

• Regularity and longer lasting - forming a noticeable pattern
• Regularity/pattern before 38 weeks - preterm labor
• Growing stronger in intensity
• Pain
• Bleeding
• Fluid leakage
• Blood tinged mucous
• Cramping or lower back ache that is constant or comes in regular waves

Braxton-Hicks contractions can be annoying and inconvenient, but generally do not cause problems or pain. It is important to know the signs and symptoms of true labor, and how to distinguish BH contractions from labor contractions. One of the best ways to get educated about that is to take a childbirth class during pregnancy. Childbirth classes teach everything from the basics of recognizing labor to the details of coping with labor pain and the many choices you will have to make surrounding your birth, postpartum, and early parenting. Childbirth classes are worth your time, money, and effort! 

References

BMJ: ADC Fetal & Neonatal Edition; "John Braxton Hicks (1823–97) and painless uterine contractions";  https://fn.bmj.com/content/81/2/F157 

American Pregnancy; "Braxton Hicks Contractions"; http://americanpregnancy.org/labor-and-birth/braxton-hicks/

The Bump; "What Are Braxton Hicks Contractions?"; https://www.thebump.com/a/braxton-hicks-contractions

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Belly Expansion During Pregnancy: What to Expect

Updated on March 11, 2021

Belly expansion is a physical manifestation of pregnancy. While your belly usually expands because of the growing baby, a few other factors are also involved. Many pregnant people wonder when and how their belly will grow. Let’s look at these common concerns and some of the more unusual causes of belly expansion during pregnancy.

When does the belly bump start to show?

Each pregnancy is different. A few things determine when your belly bump will become noticeable and how large it will be:

• Number of pregnancies

First-time mothers can expect a noticeable belly expansion between 12 and 16 weeks. Your pregnancy symptoms may include bloating and constipation, causing your waistband to feel tight even before 12 weeks. People who have been pregnant before tend to show earlier, as their abdominal wall has already stretched.

• Number of fetuses

If you’re pregnant with multiples, your bu​mp will probably be visible earlier. 

• Body composition

In people with lower body weight, a belly bump may be noticeable earlier than in overweight people. In some cases, it may not be evident until the 20th week of pregnancy.

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The bump reflects the growth of the baby above the pelvic bone. In the earlier stages of pregnancy, your uterus is still under your pelvic bone, so the expansion isn’t as noticeable.

What can belly expansion involve?

People experience several signs as their belly grows during pregnancy, and most of them are completely normal. Let's discuss them in the order they may appear.

Stretch marks

Stretch marks occur as the skin on your belly expands rapidly to accommodate the growing baby. Studies say that about 43 to 88 percent of pregnant people develop stretch marks. These show up as red or pink streaks across your tummy. Your breasts and hips, which also grow during pregnancy, may develop stretch marks too.  

Some factors influence the appearance of stretch marks:

• young age
• family history
• being overweight before pregnancy
• gaining extra weight before childbirth
• large fetal weight

Most health care providers agree that stretch marks are mostly hereditary, and topical treatment can’t stop them from occurring. However, you can try to minimize the appearance of stretch marks by maintaining a healthy diet during pregnancy. Drinking plenty of water and moisturizing regularly may also help. 

Outie belly button

Sometimes a person’s belly button may pop out as their belly expands and the umbilical tube stump pushes outward. Every pregnancy is different, so not everyone experiences these effects. Some people may even experience a certain sign with one pregnancy and not another.

Back pain

As your center of gravity shifts, your posture changes. As a result, your lower back muscles have to work harder, potentially causing chronic soreness. The abdominal muscles also influence back health by maintaining balance. During pregnancy, these muscles are stretching and cannot fully support the back. Back pain affects most people in the third trimester, when your belly is the largest. 

To minimize pain, look for comfortable shoes that support the arch of the foot, and try to avoid high heels. 

It can also be helpful to opt for clothes that support your abdomen, such as maternity pants with a wide elastic band or an abdominal binder. 

Water-based activity and swimming can help relieve symptoms of back pain.

Difficulty breathing

As the baby grows, your uterus expands into the abdominal cavity, pushing your internal organs higher underneath your rib cage. As the space in your abdomen decreases, your lungs may not be able to expand fully. The rib cage also changes its shape, making deep breaths more challenging. Studies show that around 70 percent of healthy pregnant people experience breathing difficulties. Thankfully, this resolves with the delivery of your baby. 

Rapid belly expansion: why it may occur

Other factors can influence rapid belly expansion during pregnancy.  

Date discrepancy

Your due date is measured by adding 280 days to the first day of your last period. If you’ve visited a health care provider, your due date is based on the first-trimester ultrasound. Some people who have irregular periods or did not receive an ultrasound may have additional challenges in figuring out their due date. This may make it seem like your bump is showing earlier or later than expected.

Pre-pregnancy obesity and sudden pregnancy weight gain

Health care providers generally agree that healthy people with normal body weight can expect to gain between 25 and 35 pounds during pregnancy. A lot of that weight gain will happen during the last trimester, as the baby grows more quickly.

People who gain excess weight during pregnancy may have a larger, more protruding belly. Those who were overweight or obese before conceiving may also have a larger belly bump.

Second pregnancy

Second pregnancies and beyond typically cause bumps that appear earlier. This is because the abdominal muscles have been stretched already in prior pregnancies. 

More than one baby

Mothers of multiples will often have a larger belly than women with just one fetus. After all, more babies take up more space! 

Gas and pregnancy bloating

Changes in your gastrointestinal tract are a normal part of pregnancy. Excessive gas and bloating affect lots of people, especially in the first trimester. Pregnant people may also experience constipation, especially by the second trimester. This is because of hormones that relax the intestinal muscles and the pressure of the expanding uterus on the intestines. As a result, food and waste move more slowly through your system. Increased protein intake and pregnancy vitamins with iron may also contribute to constipation.

Abnormal causes of belly expansion

In most cases, a belly bump during pregnancy is completely healthy. However, some pregnancy conditions can cause a rapidly swelling belly, requiring careful monitoring. If you experience any of these conditions, make sure to talk to a medical professional. 

1. Large fetus

A larger-than-average fetus will likely cause a larger-than-average belly bump. 

A large fetus can develop for a few reasons:

• Male fetus: Boys are born 150 grams heavier than girls, on average.
• Gestational diabetes: Maternal blood glucose levels can rise during pregnancy.
• Maternal obesity: Extra weight around the abdomen can lead to a larger bump.

Folks who have a larger baby may need additional examinations and special delivery accommodations, which need to be discussed with a health care provider as early as possible.

2. Molar pregnancy

Molar pregnancies result from problems during fertilization, leading to an abnormal placenta. In a complete molar pregnancy, the sperm has fertilized a non-viable egg, and only placental tissue develops. Because the egg wasn’t viable, no fetus develops. In a partial molar pregnancy, two sperm usually fertilize one egg, and some fetal and placental tissue begins to grow. This condition is most often diagnosed in the first trimester based on symptoms like uterine enlargement and abnormal bleeding. Most molar pregnancies result in miscarriage. 

3. Polyhydramnios

This term refers to excess amniotic fluid in the uterus. This can lead to preterm labor and contractions. Although 20 percent of cases of polyhydramnios are associated with congenital fetal abnormalities, in almost 70 percent of these pregnancies, the cause remains unknown. This condition should be closely monitored by a health care provider.

4. Large ovarian tumor

Large ovarian tumors can be spotted during routine ultrasounds during pregnancy. If you’re certain you’re not pregnant but have a fast-growing belly, your health care provider may order an ultrasound to check for large ovarian tumors. People with these tumors can develop other symptoms such as bloating, dull pain, and heaviness in the lower abdomen. Specific treatments will be determined by what the health care provider finds.

5. Fast-growing benign fibroid tumors

These occur when muscle cell fibers quickly come together into masses within the uterine wall. Despite their name, these growths are harmless and often observed on ultrasounds conducted during pregnancy.

Fibroid tumors cause abdominal swelling, pain, and difficulty urinating, all of which are similar to pregnancy symptoms. Sometimes the size of the tumor does not affect symptoms. If you’re not sure what’s causing your symptoms, contact a health care provider.

When will a belly bump disappear after delivery?

The uterus takes time to return to its pre-pregnancy size. After two weeks, it is no longer visible or felt through the abdomen, and by six weeks, its size will be roughly back to normal. As your belly shrinks, you may feel cramping and soreness. Breastfeeding your baby can help release hormones that naturally shrink your uterus.

Generally, your weight gain in pregnancy, level of activity, diet, and genetics all affect how quickly your belly returns to its pre-pregnancy size.

People who have had a C-section may experience swelling around the incision site. Scar tissue can also cause additional swelling. Individuals who gained excess weight during pregnancy, had a large fetus, or carried multiples may notice prolonged belly swelling. Generally, your weight gain in pregnancy, level of activity, diet, and genetics all affect how quickly your belly returns to its pre-pregnancy size.