Several over-the-counter options are considered safe for pregnancy constipation, including stool softeners, fiber supplements, and certain osmotic laxatives. The safest first-line choices work by staying in your gut rather than entering your bloodstream, which means very little reaches your baby. That said, it’s worth understanding why pregnancy makes you so backed up in the first place, because some simple changes can reduce how much you need to rely on medication.
Why Pregnancy Causes Constipation
High progesterone levels are the main culprit. Progesterone relaxes smooth muscle throughout your body, including the muscles that push food through your intestines. The result is slower transit time: everything moves more sluggishly, and your colon absorbs more water from stool along the way, leaving it harder and more difficult to pass. Rising estrogen levels may contribute as well by further decreasing bowel motility.
On top of the hormonal slowdown, your growing uterus physically compresses your intestines later in pregnancy. And if you’re taking a prenatal vitamin with iron (most contain ferrous sulfate), that can make constipation noticeably worse. Ferrous gluconate, a different form of iron, tends to cause fewer gut side effects. If your iron supplement seems to be the trigger, ask your provider about switching formulations.
Stool Softeners
Stool softeners like docusate sodium (Colace) are the option most commonly recommended during pregnancy. They work by drawing water into the stool so it’s easier to pass. The active ingredient is only minimally absorbed by your body, making it unlikely to affect your baby. Stool softeners are a good choice for mild to moderate constipation, though they’re not the strongest option if you haven’t had a bowel movement in several days.
Fiber Supplements
Bulk-forming laxatives like psyllium (Metamucil) and polycarbophil (FiberCon) are also considered safe because they aren’t absorbed into your bloodstream at all. They work by absorbing water in your gut and forming a gel-like bulk that stimulates your intestines to move things along. You’ll typically see results within one to three days of consistent use.
The key with fiber supplements is drinking enough water alongside them. Without adequate fluid, adding fiber can actually make constipation worse. The American College of Obstetricians and Gynecologists recommends 8 to 12 cups (64 to 96 ounces) of water daily during pregnancy. If you’re taking a fiber supplement, aim for the higher end of that range.
Osmotic and Saline Laxatives
If softeners and fiber aren’t doing the job, osmotic laxatives are the next step up. These pull water into your intestines to soften stool and stimulate a bowel movement. Osmotic medications are not well absorbed by the intestine, so very little enters your bloodstream, and exposure to the pregnancy is expected to be small.
Options in this category include magnesium hydroxide (Milk of Magnesia), magnesium citrate, and lactulose. These tend to work faster than fiber supplements and can provide relief when you’re really uncomfortable.
Stimulant Laxatives
Stimulant laxatives like bisacodyl (Dulcolax) work by triggering contractions in your intestinal muscles. They’re generally reserved for when gentler options haven’t worked. Available studies show that when used in recommended doses, over-the-counter laxatives, including stimulants, are not expected to increase the chance of birth defects. However, overusing any laxative can cause food to move through your intestines faster than normal, reducing the nutrients your body absorbs. During pregnancy, that matters more than usual.
Food-Based Remedies That Actually Help
Prunes and prune juice are the classic home remedy, and they genuinely work. Prunes are rich in sorbitol, a sugar alcohol that your gut doesn’t fully absorb. It creates an osmotic effect, pulling extra water into your intestines and loosening stool. Half a cup of prune juice twice a day is a reasonable starting point for mild constipation.
Beyond prunes, focus on high-fiber whole foods: beans, lentils, berries, pears, broccoli, and whole grains. Spreading fiber intake across the day rather than loading it into one meal helps avoid bloating and gas, which are already common complaints during pregnancy.
Probiotics for Pregnancy Constipation
There’s early evidence that certain probiotic blends can help. In a pilot study of pregnant women with constipation, a multi-strain probiotic containing several Bifidobacterium and Lactobacillus strains more than doubled weekly bowel movements after four weeks of daily use, going from about 3 per week to nearly 7. That’s a meaningful improvement, though the research is still limited. If you want to try probiotics, look for products containing Bifidobacterium and Lactobacillus strains, which are the most studied for digestive regularity.
What to Try First
A practical approach is to layer these options:
- Start with lifestyle changes. Increase water intake to at least 8 to 12 cups daily, add more fiber-rich foods, and stay physically active. Even a daily walk can help stimulate your gut.
- Add a stool softener or fiber supplement. These are the gentlest medication options and safe for daily use.
- Move to an osmotic laxative if needed. Milk of Magnesia or lactulose can provide stronger relief when softeners alone aren’t enough.
- Use stimulant laxatives sparingly. These are effective but best kept as an occasional option rather than a daily habit.
If you’ve been constipated for longer than a few weeks or are finding it consistently hard to pass stool, bring it up with your prenatal care provider. And check with them before starting any new supplement or laxative, even over-the-counter ones, just to make sure it fits with the rest of your care.