What is the best approach to manage diarrhea in a pregnant woman?

Management of Diarrhea in Pregnancy

Pregnant women with diarrhea should receive aggressive oral rehydration therapy as first-line treatment while completely avoiding antiperistaltic agents, with immediate hospitalization for intravenous fluids if severe dehydration develops. 1

Initial Assessment and Hydration Strategy

The cornerstone of management is systematic hydration assessment and replacement:

• Evaluate hydration status by checking for orthostatic hypotension, decreased skin turgor, dry mucous membranes, and obtain accurate body weight before initiating therapy 1
• For mild to moderate dehydration, initiate oral rehydration therapy with small, frequent volumes using oral rehydration salts 1, 2
• For severe dehydration (orthostatic hypotension, significantly decreased urine output, inability to tolerate oral intake), hospitalize immediately for intravenous fluid replacement and close monitoring 1, 2

Diagnostic Workup

Obtain targeted testing based on clinical presentation:

• Send stool cultures for enteroinvasive bacterial infections and Clostridioides difficile testing 1, 2
• Carefully review travel and contact history, with appropriate testing for amoebic or Shigella dysentery in patients with relevant exposures 1, 2
• If diarrhea persists beyond 5 days, high fever is present, or dysentery (bloody diarrhea) occurs, strongly consider bacterial pathogens requiring antibiotic treatment 1, 2

Antimicrobial Therapy When Indicated

Specific bacterial infections require treatment to prevent serious maternal-fetal complications:

• For pregnant women with Salmonella gastroenteritis, treatment is mandatory to prevent extraintestinal spread to the placenta and amniotic fluid, which can result in pregnancy loss 1, 2
• Appropriate antibiotic choices include ampicillin, cefotaxime, ceftriaxone, or trimethoprim-sulfamethoxazole 1, 2
• Fluoroquinolones must be completely avoided during pregnancy due to potential fetal risks 1, 2

This represents a critical divergence from non-pregnant management, where fluoroquinolones are commonly used first-line agents for bacterial gastroenteritis.

Symptom Management

For nausea and vomiting accompanying diarrhea:

• Metoclopramide can be used with less drowsiness, dizziness, and dystonia compared to promethazine 1
• Ondansetron may enhance compliance with oral rehydration therapy and decrease hospitalization rates, though use should be considered carefully before 10 weeks of pregnancy 1
• Vitamin B6 (pyridoxine) supplementation for mild nausea 1

Nutritional Support During Illness

• Continue regular diet during diarrhea with foods including starches, cereals, yogurt, fruits, and vegetables, while avoiding foods high in simple sugars and fats 2
• Give thiamine 100 mg daily for a minimum of 7 days, then 50 mg daily maintenance, to prevent refeeding syndrome and Wernicke encephalopathy until adequate oral intake is established 2

Critical Medication Pitfalls

Do not use antiperistaltic agents (such as loperamide) in pregnant women with diarrhea, as they shift focus away from appropriate fluid and electrolyte therapy and can cause serious side effects including ileus 1, 2. This is a fundamental difference from non-pregnant management where these agents are commonly used.

Thromboprophylaxis Requirements

Pregnancy creates a hypercoagulable state requiring specific prophylaxis:

• Pregnant women hospitalized for gastroenteritis should receive anticoagulant thromboprophylaxis during hospitalization, with low-molecular-weight heparin preferred over unfractionated heparin 1, 2
• Outpatients with active inflammatory bowel disease should receive VTE prophylaxis during the third trimester, unless contraindicated 1, 2

Special Considerations for Inflammatory Bowel Disease

If the patient has known IBD with suspected flare:

• Continue maintenance therapy with 5-ASA, thiopurines, systemic corticosteroids, or anti-TNF therapy throughout pregnancy 1
• Flexible sigmoidoscopy or colonoscopy may be performed if results will affect antenatal management 1, 2
• Limit radiologic investigations to ultrasound and MRI where possible, avoiding gadolinium 1, 2
• Do not delay urgent surgery to manage complications solely due to pregnancy 1, 2

When to Escalate Care Immediately

Instruct patients to return or call immediately if:

• Decreased urine output or inability to maintain hydration orally develops 2
• Persistent high fever or bloody diarrhea occurs 2
• Signs of severe dehydration appear (orthostatic symptoms, confusion, minimal urine output) 1

Prevention of Household Transmission

• Household contacts of pregnant women with salmonellosis or shigellosis should be evaluated for asymptomatic carriage to prevent recurrent transmission 2