Constipation in pregnancy is common, and it can start early. Pregnancy hormones are thought to slow your bowel down, and iron tablets can add to it [2][3]. The reassuring part: simple fixes like fibre, fluids and gentle movement are safe to try while pregnant [1].
Constipation is common during pregnancy and after giving birth [1]. Pregnancy hormones may relax the bowel muscles and slow things down, and iron supplements can make it worse [2][3]. NHS advice is that diet and lifestyle changes are safe to try in pregnancy, but check with your midwife, GP or pharmacist before taking a laxative [1][4].
Why does constipation happen in pregnancy?
Pregnancy hormones act to relax muscles and may slow the movement of food through the gut [2]. Some people notice it early: NHS guidance for weeks 9 to 12 mentions that you might find you are a bit constipated [5]. Iron tablets, often prescribed in pregnancy, list constipation and darker poo among common side effects [3]. Not sure what is normal for you? See how often you should poo.
What helps constipation in pregnancy?
The NHS says its simple measures are safe to try when you are pregnant [1]. Gradually increase fibre, drink plenty of water and other fluids, and include fruits containing sorbitol such as apples, apricots, grapes, raspberries and strawberries [1]. Here is why hydration and digestion go together, and more on fibre and gut health.
Keep a regular toilet time, do not delay when you feel the urge, and rest your feet on a low stool so your knees sit above your hips [1]. Read more on the best position to poop. A daily walk may help you poo more regularly too [1]; check with your midwife if you have been advised to rest.
Which laxatives are safe in pregnancy?
Not all laxatives you can buy are suitable for use in pregnancy, so discuss any laxative with your midwife or doctor first [4]. A pharmacist can also suggest a suitable option; most laxatives work within three days and are meant for short-term use [1]. Food-first ideas are in our guide to natural laxatives, but check with your midwife before trying anything new.
| What to try | Why it may help | Check first? |
|---|---|---|
| Building up fibre gradually | Makes poo softer and easier to pass [1] | No |
| Plenty of water and other fluids | Part of NHS self-care advice [1] | No |
| A low stool under your feet | May make it easier to poo [1] | No |
| A daily walk | May help you poo more regularly [1] | Yes, if you have been advised to rest |
| Laxatives | Can help if lifestyle changes are not enough [1] | Yes, not all are suitable in pregnancy [4] |
When to get help
Call your maternity unit immediately if you have stomach pain and:
- vaginal bleeding or spotting
- regular cramps or tightenings and you are less than 37 weeks pregnant
If the pain or bleeding is severe, call 999. If your maternity unit is not available, call 111 [6].
See your GP or midwife if: you have blood in your poo, your constipation is not getting better with treatment, or you have tummy pain [1].
If you take iron: talk to a doctor or call 111 straight away if your poo is black and tar-like, red, or has blood in it [7].
Constipation in pregnancy: your questions answered
Is constipation an early sign of pregnancy?
It can happen early. NHS guidance for weeks 9 to 12 notes that some people notice they are a bit constipated [5], and hormones are thought to play a part [2]. But constipation has many causes, so on its own it is not a reliable sign. A pregnancy test will give you a clear answer.
Can iron tablets cause constipation in pregnancy?
Yes. Constipation and darker than usual poo are common side effects of iron tablets such as ferrous fumarate [3]. Do not stop taking them without advice; your midwife or GP may be able to suggest ways to cope with side effects. Poo that is black and tar-like, red, or bloody needs a call to a doctor or 111 straight away [7].
Will constipation continue after the birth?
It might for a while. The NHS notes constipation is common after giving birth as well as during pregnancy [1]. The same gentle measures still apply, and your midwife or GP can advise on laxatives that are suitable if you are breastfeeding. Our guide to postpartum gut health looks at the months after birth.
Be gentle with yourself. Start with a glass of water and a fibre-rich breakfast, take a short walk if you feel up to it, and give yourself unhurried time on the loo with your feet raised. If things are not settling, or you think you need a laxative, ask your midwife or pharmacist what is suitable for pregnancy.
References
- NHS. Constipation. Last reviewed 26 October 2023. nhs.uk/conditions/constipation
- MotherSafe, Royal Hospital for Women (NSW Health). Constipation in pregnancy. 2019. Note: Australian guidance.
- NHS. Side effects of ferrous fumarate. nhs.uk
- Manchester University NHS Foundation Trust. Medications advice for patients admitted to the maternity wards.
- NHS 111 Wales. Pregnancy: 9 to 12 weeks. 111.wales.nhs.uk
- NHS. Stomach pain in pregnancy. nhs.uk
- NHS. Side effects of ferrous sulfate. nhs.uk
This content is for informational purposes only and does not constitute medical advice. If you have concerns about your digestive health, please speak to a qualified healthcare professional.
