What are the management options for constipation in pregnancy?

Management of Constipation in Pregnancy

Constipation in pregnancy should be treated with dietary fiber, adequate hydration, and if needed, bulk-forming agents like psyllium or osmotic laxatives such as polyethylene glycol (PEG) as first-line treatments. 1, 2

Understanding Constipation in Pregnancy

Constipation affects approximately 20-40% of pregnant women and is attributed to several factors:

• Increased progesterone levels slowing gastrointestinal motility
• Physical compression from the growing uterus
• Iron supplementation (common in pregnancy)
• Reduced physical activity
• Inadequate fluid intake

Treatment Algorithm

First-Line Approaches (Non-Pharmacological)

1. Dietary modifications:

   • Increase dietary fiber intake to approximately 30g/day (fruits, vegetables, whole grains, legumes)
   • Ensure adequate fluid intake, particularly water
   • Allow sufficient time for bowel movements
   • Use relaxation techniques to avoid straining

2. Physical activity:

   • Regular, moderate exercise as tolerated and approved by healthcare provider

Second-Line Approaches (Safe Pharmacological Options)

If dietary and lifestyle modifications are insufficient:

1. Bulk-forming agents (first choice):

   • Psyllium husk (6.8-10.8g daily with 8-10 oz of fluid) 2
   • Safe in pregnancy due to lack of systemic absorption 1
   • Take immediately before meals rather than between meals

2. Osmotic laxatives (if bulk-forming agents fail):

   • Polyethylene glycol (PEG) 17g daily mixed with 8 oz of liquid 2, 3
   • Lactulose (alternative osmotic option) 4
   • PEG shows advantages with faster onset and fewer flatulence issues 4

3. Stool softeners:

   • Docusate sodium - considered safe but limited efficacy data 4

Third-Line Approaches (Use with Caution)

For refractory cases only, after second trimester:

• Stimulant laxatives (short-term use only):
  • Bisacodyl or sodium picosulfate in second and third trimesters 4
  • Senna - limited use and only under medical supervision 5, 6
  • Caution: May cause dehydration or electrolyte imbalances with prolonged use 7

Important Considerations and Caveats

• Timing matters: Bulk-forming agents should be taken with adequate fluid to prevent esophageal obstruction 2

• Duration of treatment: PEG should be used for 2 weeks or less unless directed by a physician 3

• Medication warnings:

  • Do not use stimulant laxatives for longer than one week unless directed by a doctor 5
  • Prolonged, frequent or excessive use of PEG may result in electrolyte imbalance and laxative dependence 3

• Pregnancy-specific concerns:

  • Stimulant laxatives may cause tenesmus (painful straining) which could be associated with preterm birth risk 4
  • Avoid medications that could cause dehydration

• When to seek medical attention:

  • Rectal bleeding
  • Failure to have bowel movement after laxative use
  • Severe abdominal pain
  • Symptoms persisting despite appropriate treatment

Evidence Quality Assessment

The recommendations are based primarily on expert consensus and observational studies, as few randomized controlled trials have been conducted specifically for constipation treatment in pregnancy. The American Gastroenterological Association guidelines 1, 2 provide the strongest evidence for the safety of bulk-forming agents and osmotic laxatives during pregnancy.

A Cochrane review found that fiber supplements increased the frequency of defecation and led to softer stools, while stimulant laxatives were more effective than bulk-forming laxatives but caused more side effects 6.

Most laxatives have minimal systemic absorption and are therefore not expected to increase the risk of congenital anomalies 7, but caution is still warranted.