Constipation is one of the most common discomforts of pregnancy, affecting roughly 40% of pregnant women at some point. It can show up as early as the first trimester and persist through delivery, so if you’re dealing with it, you’re far from alone.
How Common It Is by Trimester
Constipation can strike at any stage, but it tends to peak early. Symptoms are reported most frequently in the first trimester, when hormonal shifts are most dramatic. Looking at the numbers across pregnancy, about 24% of women experience constipation in the first trimester, 26% in the second, and 16% in the third. Interestingly, it can even linger after birth: roughly 24% of women still report constipation three months postpartum.
The dip in the third trimester might seem surprising, since that’s when the uterus is largest. But many women have adjusted their diet and habits by then. Still, the overall picture is clear: constipation is a normal, expected part of pregnancy for a large percentage of women.
Why Pregnancy Slows Your Digestion
Several things work together to make your bowels sluggish during pregnancy. The biggest factor is hormonal. Rising progesterone levels relax smooth muscle throughout your body, including the muscles that move food through your intestines. This means everything travels more slowly, and more water gets absorbed from stool along the way, leaving it harder and more difficult to pass.
In the third trimester, there’s also a physical component. The growing uterus presses directly on the intestines, which can slow things down further. This pressure can also contribute to hemorrhoids, which sometimes develop alongside chronic constipation and make bowel movements uncomfortable.
Iron supplements are another major contributor. Prenatal vitamins often contain iron, and constipation is a well-known side effect. If your constipation worsened noticeably after starting a prenatal vitamin or a separate iron supplement, that connection is worth raising with your provider. Switching to a different form of iron or adjusting the dose can sometimes help.
What You Can Do About It
Fiber and Fluids
The first line of defense is dietary. Pregnant women need about 25 to 28 grams of fiber per day, which is more than many people get without paying attention. Good sources include fruits, vegetables, whole grains, beans, and lentils. If you’re not used to eating much fiber, increase your intake gradually over a week or two to avoid bloating and gas.
Water matters just as much. Fiber works by absorbing water and adding bulk to stool, so increasing fiber without drinking enough fluid can actually make constipation worse. Aim to drink consistently throughout the day rather than trying to catch up all at once.
Regular Movement
Exercise is one of the most effective and overlooked tools for keeping your bowels moving. Physical activity stimulates the muscles in your intestines, helping food and waste travel through more efficiently. Walking, swimming, and cycling are all good options during pregnancy. Start with 15 minutes a day if you’re not already active, and work up to 30 minutes. Exercising at least three to five times per week gives the best results for both bowel regularity and overall pregnancy health.
Stool Softeners and Laxatives
When lifestyle changes aren’t enough, several over-the-counter options are considered safe during pregnancy. Stool softeners like docusate sodium moisten the stool and make it easier to pass without forcing a bowel movement. They’re often the first thing providers recommend because they’re gentle and not absorbed into the bloodstream.
Bulk-forming laxatives containing psyllium (the active ingredient in products like Metamucil) work similarly to dietary fiber, adding bulk and drawing water into the stool. These are also not absorbed by the body, which is why they’re generally considered safe.
For more stubborn constipation, saline laxatives like magnesium hydroxide (Milk of Magnesia) or stimulant laxatives are sometimes used. These are stronger, so they’re better suited for occasional use rather than daily reliance. Your provider can help you figure out which option makes sense for your situation.
Signs That Need Medical Attention
Garden-variety constipation during pregnancy, while uncomfortable, isn’t dangerous. But certain symptoms alongside constipation warrant a call to your provider: blood in the stool, severe abdominal pain or cramping, vomiting, unexplained weight loss, or constipation that doesn’t improve at all with dietary changes and increased fluids. Blood in the stool is often from hemorrhoids, which are common in pregnancy, but it should still be evaluated to rule out other causes.