Constipation in Pregnancy

There are several factors that contribute to constipation in pregnancy. The hormone progesterone increases, which causes the bowel to relax, which then slows down the movement of poo through your gut. As food remains longer in the bowel, more and more nutrients and water get removed from it, making it harder and more difficult to pass.

As your baby grows and takes up more room in the abdominal space, this puts pressure on your bowel, which is why constipation is most common in the third trimester.

Some people are less active during pregnancy and drink less water, which worsens constipation. Medications like iron tablets, which are commonly taken in pregnancy, can cause constipation as a side effect.

The good news is that while uncomfortable and sometimes painful, constipation does not harm the baby. Complications of constipation, like haemorrhoids and anal fissures, can make normal vaginal delivery more uncomfortable. But with the right steps, it’s perfectly possible in your birth plan to accommodate for this.

Make sure you’re packing in the fibre-rich food – the aim is 30g of fibre per day, but it’s hard to quantify, so aim for lots of fruit and vegetables, wholegrains, lentils and beans.

It's essential to drink plenty of water, around 1.5 to 2 litres per day, especially in pregnancy. This softens your stool and keeps you feeling well. Keeping active helps to keep the bowel active – make sure any exercise is pregnancy-safe and matches your energy levels - walking or swimming can be good, or pregnancy yoga.

The good news is that for most women, constipation improves in the days and weeks after delivery. But keep going with the things you know can help, while your body readjusts in the post-partum recovery.

Laxatives are a general term for constipation relief. They fall into different categories, depending on how they work. Let’s give you a rundown of each, and let you know what’s safe in pregnancy and what’s to be avoided.

Osmotic laxatives work by osmosis and draw water with them as they move from the stomach and into the large bowel. They work best if constipation has been a problem for less than 3 days. They take about 24 to 48 hours to get to work. They have a gentle action and are safe to use for a few weeks. Lactulose solution can be a good place to start – try taking 15ml twice a day with a glass of water. Movicol sachets containing macrogol powder are another option – dissolve one or two in a glass of water twice daily.

Bulk-forming laxatives act by adding soluble fibre to stools to give them volume. They keep stools soft and loose, making them easier to pass. This helps prevent or ease piles (haemorrhoids), which are common in pregnancy, and will help those who don’t get enough fibre.

Fybogel satchets containing isphagula husk are one example - adults should take 1 sachet in a glass of water twice daily. Again, they are best used if you’ve had constipation for less than 3 days, and take 24 to 48 hours to take effect. Fybogel is mild enough to take routinely for a few weeks.

Glyerol or glycerin suppositories are particularly effective when other treatments have failed or when stools are difficult to pass. They work directly in the rectum, and results are usually seen within an hour, or you can add them on to other treatments.

There are certain laxatives you should avoid during pregnancy and in the post-partum stage after delivery. Stimulant laxatives such as senna and bisacodyl tablets (in brands Senokot or Dulcolax) work by forcing stools down and out. They work fairly quickly (within 8 to 12 hours). They should be avoided during pregnancy due to the possibility of causing abdominal cramps.

Stool softeners containing docusate sodium, such as Dulcoease, should only be used during pregnancy if the benefits outweigh the risks. This should be done in consultation with your doctor. They are not recommended in breastfeeding as docusate sodium and its metabolites are secreted into breast milk, which may present a risk.

It's important to check with your pharmacist or doctor before trying any supplements from health shops or products claiming to be natural remedies, as they may not have been rigorously tested and therefore deemed safe for pregnant women. Castor oil, for example, is to be avoided in pregnancy.