Postpartum Constipation

Postpartum constipation is infrequent, hard or difficult passage of stool (fewer than 3 stools a week, or straining) in the weeks after birth. It is common in the first week and results from opioids, iron tablets, dehydration, fear of pain from perineal wounds or haemorrhoids, reduced activity and hormonal change. It matters because straining damages perineal repairs, aggravates haemorrhoids and fissures, and causes distress.

• Risk factors: caesarean section, perineal tears, opioids, ferrous sulphate, low fibre diet, poor fluid intake, bed rest, haemorrhoids, anal fissure.
• Most women are normal again by 6 weeks.
• Early mobilisation and fluids prevent most cases.

Women have hard stools, straining, a sense of incomplete emptying, abdominal bloating and discomfort, and fear of passing stool. Hard stool in the rectum may be felt on examination.

• Fewer than 3 stools a week.
• Abdominal distension and left iliac fossa fullness.
• Differential diagnosis: postcaesarean ileus, rectal prolapse, anal fissure, thrombosed haemorrhoids, intestinal obstruction, hypothyroidism, hypercalcaemia, drug effect.
• Complications: haemorrhoids, anal fissure, faecal impaction with overflow, perineal wound breakdown, rectal prolapse, urinary retention, pain.

The approach is history, examination and exclusion of other causes.

• Stool frequency and consistency (Bristol scale), diet, fluids, drugs (opioids, iron), pain on defaecation, bleeding.
• Abdominal examination for distension and masses; perineal and digital rectal examination for fissure, haemorrhoids, impaction and sphincter injury.
• Thyroid function and calcium if constipation is persistent.
• Abdominal X-ray only if obstruction or ileus is suspected.

The principle is diet, fluids and a stepwise laxative plan, with no straining after a perineal repair.

• Supportive: fibre 25 to 30 g daily (fruit, vegetables, whole grains, beans); fluids 2 to 3 litres daily; early mobilisation; regular toilet routine after meals; footstool to raise the knees when sitting; hold a pad against the perineal repair when passing stool; take iron with food or change to alternate days.
• Pharmacological: lactulose 15 mL oral 12-hourly; ispaghula husk 3.5 g oral 12-hourly with a full glass of water; bisacodyl 10 mg oral at night if no stool in 3 days; glycerin suppository 4 g rectally as needed; docusate sodium 100 mg oral 12-hourly for hard stool; enema (sodium phosphate 133 mL rectally once) for impaction; ferrous sulphate 200 mg oral once daily or on alternate days.
• Procedures: manual evacuation of faecal impaction under analgesia if enemas fail.
• Special groups: women with a third or fourth degree tear take lactulose 15 mL oral 12-hourly and ispaghula husk 3.5 g oral 12-hourly for 10 to 14 days and avoid enemas and suppositories.
• Red flags: severe abdominal pain, vomiting, distension with no flatus, rectal bleeding, fever, leaking stool, no stool for 5 days.
• Follow-up: review at 1 week; review at 6 weeks; thyroid test and colon assessment if constipation continues beyond 3 months.