Changes in bowel habits during pregnancy

Hormonal changes can slow movement through the gut, while iron supplements may make stools harder or darker. Changes in food, fluid intake, activity, nausea, or prenatal medicines can also affect frequency and consistency. Loose stools may instead follow an infection or a food that did not agree with you.

An ongoing change in bowel habit can occur with bowel or rectal cancer, although pregnancy-related and non-cancerous explanations are more commonly considered in this setting. The symptom needs individual assessment when it persists or occurs with bleeding, unexplained weight loss, a new lump, or continuing abdominal pain.

For constipation, fluids, fibre-rich foods, and gentle movement may help if your maternity clinician has not advised restrictions. Increase fibre gradually to limit bloating. For loose stools, replace fluids and choose simple foods you can tolerate.

Check with a pharmacist, obstetrician, or midwife before using laxatives, anti-diarrhoeal products, herbal remedies, or supplements during pregnancy. Record when the change started, stool appearance, pain, vomiting, fever, blood, recent meals, travel, and all medicines. This helps the maternity team choose suitable care.

Get urgent help for severe or one-sided abdominal pain, heavy rectal bleeding, fainting, confusion, repeated vomiting with inability to drink, very little urine, or symptoms accompanied by vaginal bleeding, fluid leakage, regular tightening, or reduced fetal movement.

Contact your maternity team soon if constipation is painful and does not improve, diarrhoea continues, blood appears in the stool, fever develops, or you cannot maintain hydration. If you are receiving cancer treatment, report bowel changes promptly because infection and dehydration may require early treatment.

Ask whether an iron preparation or another medicine could explain the change, which remedies are appropriate at your stage of pregnancy, and whether examination or tests are needed. Confirm whom to contact if symptoms worsen outside normal clinic hours.