What precautions should a 24-week pregnant woman take when experiencing a stomach bug (gastroenteritis)?

Management of Gastroenteritis in a 24-Week Pregnant Woman

A pregnant woman at 24 weeks with gastroenteritis should prioritize aggressive hydration, obtain stool cultures for bacterial pathogens and Clostridioides difficile, and seek immediate medical attention if severe dehydration develops, as maternal dehydration poses significant risks to both mother and fetus. 1

Immediate Assessment and Diagnostic Workup

Obtain stool testing for the following pathogens to guide management: 2, 1

• Stool cultures for enteroinvasive bacterial infections (Salmonella, Shigella, Campylobacter)
• Clostridioides difficile assay
• If travel history is present, test specifically for amoebic dysentery or Shigella 2

Monitor for warning signs requiring hospitalization: 1

• Severe dehydration (orthostatic hypotension, decreased skin turgor, reduced urine output)
• Inability to maintain oral hydration
• Persistent vomiting preventing fluid intake
• Fever ≥100.4°F (≥38.0°C) 2
• Severe abdominal pain or signs of peritoneal irritation

Hydration Management

Oral rehydration is the cornerstone of treatment for mild to moderate cases: 1, 3

• Encourage frequent small sips of clear fluids, oral rehydration solutions, or electrolyte-containing beverages
• Avoid large volumes at once, which may trigger vomiting
• Target adequate urine output as a marker of hydration status

Hospitalization with IV fluid replacement is mandatory if: 1

• Severe dehydration is present
• Oral intake is not tolerated
• Signs of maternal or fetal compromise develop

Dietary Modifications

Implement the BRAT diet during acute symptoms: 2

• Bananas, rice, applesauce, and toast
• Small, frequent, bland meals
• High-protein, low-fat options as tolerated
• Avoid spicy, fatty, acidic, and fried foods 2

Antimicrobial Therapy Considerations

If Salmonella gastroenteritis is confirmed, antibiotic treatment is recommended to prevent extraintestinal spread, which poses particular risks in pregnancy: 1

• Safe options: ampicillin, cefotaxime, or ceftriaxone
• Avoid fluoroquinolones (ciprofloxacin, levofloxacin) during pregnancy due to fetal risks 1
• TMP-SMZ may be used but avoid in first trimester and near term

For other bacterial pathogens, treatment decisions should be guided by stool culture results and severity of illness 1

Symptomatic Management

Antiemetic therapy if nausea/vomiting is prominent: 2

• First-line: Vitamin B6 (pyridoxine) 10-25 mg every 8 hours
• Second-line: Doxylamine 10-20 mg (can be combined with pyridoxine)
• Alternative: Promethazine or dimenhydrinate if first-line agents fail

Antidiarrheal agents should be used cautiously: 4

• Generally avoid in acute infectious diarrhea as they may prolong pathogen clearance
• May consider mild agents only after infectious causes are ruled out

Imaging Precautions

If imaging is required to evaluate complications (rare in simple gastroenteritis): 2

• Prioritize ultrasound as first-line imaging modality
• MRI without gadolinium is acceptable if ultrasound is inadequate
• Avoid gadolinium-enhanced MRI during pregnancy 2
• Minimize radiation exposure; avoid CT unless absolutely necessary for life-threatening complications

Thromboembolism Prophylaxis

If hospitalization is required: 2

• Administer anticoagulant thromboprophylaxis during hospitalization
• Pregnancy increases VTE risk, which is further elevated by dehydration and immobility
• Continue prophylaxis throughout hospital stay

Monitoring and Follow-up

Assess for household transmission: 1

• Evaluate household contacts for asymptomatic carriage of Salmonella or Shigella to prevent recurrent transmission
• Implement strict hand hygiene and food safety measures

Monitor fetal well-being if maternal illness is severe: 1

• Fetal heart rate monitoring if maternal fever or significant dehydration
• Ensure adequate maternal hydration to maintain uteroplacental perfusion

Red Flags Requiring Urgent Evaluation

Seek immediate medical attention if any of the following develop: 2, 1, 5

• Persistent fever ≥100.4°F (≥38.0°C)
• Bloody diarrhea
• Severe abdominal pain or peritoneal signs
• Signs of preterm labor (regular contractions, pelvic pressure)
• Decreased fetal movement
• Inability to maintain hydration despite oral attempts
• Altered mental status or severe weakness

Common Pitfalls to Avoid

Do not use fluoroquinolones (ciprofloxacin, levofloxacin) despite their common use in non-pregnant adults with gastroenteritis 1

Do not delay appropriate antibiotic therapy for confirmed Salmonella infection, as extraintestinal spread poses serious maternal and fetal risks 1

Do not assume symptoms are "just pregnancy-related" without proper evaluation—obtain stool studies to identify treatable pathogens 2, 1

Do not underestimate dehydration risks—pregnant women require more aggressive hydration than non-pregnant patients due to increased plasma volume and fetal needs 1, 3