Constipation Relief When Pregnant: What's Safe
Constipation affects a large proportion of pregnancies, and it's one of the symptoms people are least prepared for. It's also one where the usual advice doesn't apply, because several common remedies aren't suitable while you're pregnant.
Here's why it happens, which options are generally considered suitable, what to avoid outright, and when to pick up the phone.
Pregnancy constipation is driven by raised progesterone slowing the gut, physical pressure from the growing uterus, and iron supplements. Start with food, fluid and gentle movement. Bulk-forming fibre such as psyllium, and osmotic options like polyethylene glycol or lactulose, are the ones usually considered suitable — but check with your midwife or doctor first. Avoid stimulant laxatives, castor oil, mineral oil and herbal cleanse products entirely.
Why it happens
Progesterone. The main driver. Progesterone relaxes smooth muscle throughout the body, including the muscle in your intestinal wall, which slows how quickly things move through. It rises early and stays high, which is why constipation can start in the first trimester.
Physical pressure. As the uterus grows it presses on the bowel, and that becomes more significant in the third trimester.
Iron supplements. Prenatal vitamins and standalone iron are both commonly constipating, and iron is frequently the single biggest contributor. This is the most actionable item on the list — see below.
More water going elsewhere. Blood volume increases substantially in pregnancy, and fluid demands rise with it. If intake doesn't keep up, the colon reabsorbs more water from stool.
Less movement. Fatigue, nausea, discomfort and advice to take it easier all reduce activity, and activity affects bowel transit.
Pelvic floor changes. Later in pregnancy, the mechanics of passing stool change, and that can make it harder even when consistency is fine.
Start with iron
If you take iron and you're constipated, this is where the biggest single improvement usually lives — and it's worth raising specifically rather than assuming nothing can change.
Things your midwife or doctor may be able to adjust:
- A different form of iron. Ferrous gluconate and iron bisglycinate are often better tolerated than ferrous sulphate.
- Alternate-day dosing. There's reasonable evidence that taking iron every other day can improve absorption while reducing side effects.
- Checking whether you need it. Not everyone on a prenatal vitamin needs additional iron; a blood test answers it.
- Taking it with vitamin C and away from tea, coffee, calcium and antacids, which improves absorption and may allow a lower dose.
Don't stop iron on your own. Iron deficiency in pregnancy matters, and the answer is usually an adjustment rather than stopping.
Food and fluid first
Unglamorous, and it's where to begin.
Fibre toward 25–30 g a day, built up gradually rather than all at once. Oats, lentils, beans, pears, berries, kiwi fruit, chia seeds, ground flaxseed and wholegrains all contribute.
Prunes have better evidence than most options and are a reasonable first thing to try — around five or six prunes, or a glass of prune juice. They combine fibre with sorbitol, which draws water into the bowel.
Kiwi fruit — two a day has trial support for improving stool frequency and consistency, with less bloating than many fibre approaches.
Fluid. More than you think, and more than before pregnancy. Fibre without adequate water makes constipation worse rather than better.
Warm drinks in the morning work with the body's natural reflex after the first meal.
Movement and positioning
Walking, swimming and pregnancy-appropriate yoga all help transit, and anything your midwife has cleared is worth doing regularly rather than occasionally.
For positioning: a small footstool to raise the knees above the hips changes the anatomy favourably, and avoid straining — it contributes to haemorrhoids, which are already more common in pregnancy.
Take unhurried time after breakfast, and go when you feel the urge rather than waiting.
What's generally considered suitable
Every item here comes with the same caveat: check with your midwife, obstetrician or pharmacist before starting anything. Individual circumstances differ, and they know yours.
| Option | Generally regarded as | Notes |
|---|---|---|
| Dietary fibre, prunes, kiwi | First choice | Food-based; no reason to wait |
| Psyllium, methylcellulose (bulk-forming) | Usually suitable | Not absorbed; needs plenty of water |
| Polyethylene glycol (osmotic) | Commonly used in pregnancy | Minimally absorbed; often first-line if fibre isn't enough |
| Lactulose (osmotic) | Commonly used in pregnancy | Can cause wind and bloating |
| Glycerin suppository | Sometimes used | Acts locally; ask first |
| Docusate (stool softener) | Sometimes used | Evidence of effectiveness is weak generally |
| Senna | Only if specifically advised | A stimulant; sometimes used short-term postpartum under guidance |
Bulk-forming fibre is usually the preferred supplement route because it isn't absorbed into your bloodstream at all — it works mechanically in the gut. The fluid requirement is strict, though: a full glass with each dose and more across the day. Our guide to taking psyllium husk properly covers the technique, and our comparison of fibre supplements explains how the types differ.
What to avoid
These matter, and two of them are actively dangerous rather than simply unsuitable.
Castor oil. Avoid entirely. It's a traditional folk remedy for inducing labour, and that's precisely the problem — it can cause uterine contractions. It also causes severe cramping and dehydration. Never use it in pregnancy.
Mineral oil (liquid paraffin). Avoid. It interferes with absorption of fat-soluble vitamins — including vitamin K, which matters for both you and the baby — and carries an aspiration risk.
Stimulant laxatives. Senna, bisacodyl, cascara sagrada, buckthorn, rhubarb root and aloe latex. Not suitable in pregnancy without specific medical advice. They cause cramping and fluid loss, and anthraquinones are the class generally advised against.
Herbal cleanse, detox and "colon cleanse" products. Avoid as a category. They typically combine several stimulant laxatives with other botanicals, often in undisclosed amounts, and several of those botanicals have their own pregnancy cautions. Goldenseal is a common one and is specifically advised against — it contains berberine, which can interfere with how bilirubin is handled in newborns.
Magnesium citrate and saline laxatives. Not a first choice; ask before using.
Enemas. Only if specifically advised by your care team.
High-dose herbal supplements generally. "Natural" carries no safety guarantee in pregnancy, and many botanicals simply haven't been studied in pregnant women. Run anything past your midwife.
Haemorrhoids: the common companion
Haemorrhoids are very common in pregnancy, caused by the combination of increased pelvic pressure, higher blood volume and straining.
The most effective approach is preventing the straining in the first place — softer, bulkier stool, a footstool, not lingering on the toilet, and going when you feel the urge. Fibre is first-line here too.
For symptoms, your midwife or pharmacist can advise on which topical treatments are suitable during pregnancy. Any rectal bleeding should be mentioned to your care team rather than assumed to be haemorrhoids, even though that's the most likely explanation.
Postpartum constipation
Often worse than during pregnancy, and rarely discussed in advance.
Contributing factors include the effects of labour on the pelvic floor, perineal tearing or stitches, fear of the first bowel movement, caesarean recovery, opioid pain relief, dehydration from breastfeeding, and continued iron supplementation.
Practical measures: keep fluid high, keep fibre up, use a footstool, support the perineum with a clean pad when you go, and ask about a stool softener or laxative before you leave hospital rather than afterwards. Opioid pain relief in particular almost always needs something alongside it.
While breastfeeding, the same cautions broadly apply — bulk-forming and osmotic options are generally preferred, and anthraquinone stimulants can pass into breast milk in small amounts. Goldenseal is advised against while breastfeeding for the berberine reason above. Check anything new with your midwife, health visitor or doctor.
When to call your midwife or doctor
- Severe or persistent abdominal pain
- Rectal bleeding
- No bowel movement for several days with abdominal distension
- Vomiting
- Constipation that hasn't responded to diet, fluid and movement
- Before starting any laxative or new supplement
- Constipation alternating with diarrhoea
- Painful haemorrhoids, or any bleeding from them
Pregnancy is the one situation where it's entirely reasonable to ask about something minor. Your midwife would much rather field a question about constipation than have you guess.
About our own product
Plainly: Colon Sweep is not for use during pregnancy or breastfeeding.
It's a herbal stimulant laxative formula. Its blend contains four anthraquinone stimulants — cascara sagrada bark, buckthorn bark, rhubarb root and aloe vera leaf — all of which fall into the class generally advised against in pregnancy. It also contains goldenseal root, which is specifically advised against in pregnancy and while breastfeeding.
We'd rather say that clearly than bury it in small print, and we'd rather you used the suggestions above and spoke to your midwife. If you're pregnant and constipated, none of our products is the answer to that.
The bottom line
Pregnancy constipation comes mainly from progesterone slowing the gut, physical pressure, and iron supplements — and iron is often the most fixable part, so raise it with your midwife rather than accepting it.
Build fibre gradually, drink more than feels necessary, move regularly, use a footstool and don't strain. Prunes and kiwi fruit are worth trying early. If you need something from a bottle, bulk-forming fibre or an osmotic laxative are the options usually considered suitable — after a conversation with your care team. Avoid castor oil, mineral oil, stimulant laxatives and herbal cleanse products entirely, and ring your midwife about bleeding, severe pain or anything that isn't improving.
These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease. This article is for general information and is not a substitute for medical advice. It is not personalised pregnancy advice — consult your midwife, obstetrician, doctor or pharmacist before taking any laxative, supplement or herbal product during pregnancy or while breastfeeding. Do not stop prescribed iron or any other prescribed medication without medical advice. Do not use castor oil or mineral oil in pregnancy. Contact your midwife or doctor about rectal bleeding, severe abdominal pain, vomiting, or constipation that is not improving. The product mentioned in this article is not for use during pregnancy or breastfeeding. Keep out of reach of children.
