Loose stools in pregnancy: causes, hydration and warning signs

The usual causes

Infection: viral gastroenteritis or food poisoning, which is the commonest cause and usually settles in a day or two. In India this rises sharply in the monsoon and with eating out.

Diet and supplements: a change in eating, an excess of fruit or fibre, or the magnesium in some prenatal supplements.

Hormonal effects on the gut, which more often cause constipation but can swing the other way.

Near term: loose stools in the last days before labour are common and are the body's own preparation. Combined with regular tightening, that is worth mentioning.

And less commonly: irritable bowel disease, thyroid problems, or an intolerance that has become more noticeable.

What to do

Fluids first. ORS mixed exactly as directed is the correct treatment; sip constantly rather than drinking a glass at once. Coconut water, chaas and rice kanji all help.

Eat bland and simple: khichdi, curd rice, banana, toast, dal-rice. Do not starve — it delays recovery.

Avoid: anti-diarrhoeal medicines unless your doctor prescribes them, antibiotics without prescription, and any herbal remedy not cleared for pregnancy.

Rest, and keep taking folic acid and iron unless the iron is clearly worsening things, in which case ask rather than stopping.

Watch the hydration signs: dark scanty urine, dizziness on standing, a dry mouth and a racing heart all mean you are behind on fluids, and dehydration in pregnancy can trigger contractions.

When to see a doctor

Go to hospital immediately at any stage for: heavy bleeding, severe or constant abdominal pain, a gush or steady trickle of fluid, severe headache with visual changes, sudden swelling of the face and hands, high fever, fainting, or reduced fetal movements after 28 weeks. Call 108 if you cannot travel quickly.

Same-day: diarrhoea lasting more than 24 to 48 hours, blood or mucus in the stool, fever, severe abdominal pain, vomiting alongside so you cannot keep fluids down, signs of dehydration, or diarrhoea with regular tightening or cramping before 37 weeks — dehydration and infection can both trigger preterm labour.

Also same-day if you have recently travelled, eaten out and become unwell, or if someone in the household has a similar illness — some causes need specific treatment in pregnancy.

This article is general information, not medical advice, and is no substitute for personal medical advice. For any decision about your or your child's health, please consult your doctor.

Frequently asked questions

Q: Can loose motions cause a miscarriage? — Not directly. The risk comes from dehydration and from certain infections, which is why fluids and assessment matter.

Q: Is ORS safe in pregnancy? — Yes, and it is the right treatment. Mix one sachet in exactly one litre of clean boiled-and-cooled water.

Q: I am 38 weeks with loose stools. Is labour starting? — It can be a sign that labour is near, particularly with cramping or tightening. Call your hospital and describe it rather than waiting to see.

Q: Which anti-diarrhoeal is safe? — Ask your obstetrician. Several common ones are avoided in pregnancy, and the first-line treatment is fluids rather than a tablet.