What is the recommended management for influenza in pregnancy?

Management of Influenza in Pregnancy

Pregnant women with suspected or confirmed influenza should receive prompt treatment with oral oseltamivir (75 mg twice daily for 5 days) regardless of vaccination status, with treatment initiated as soon as possible after symptom onset. 1

Vaccination Recommendations

Influenza vaccination is the primary preventive strategy for pregnant women:

• Inactivated influenza vaccine (IIV) or recombinant influenza vaccine (RIV) is recommended for all pregnant women during any trimester 2, 1
• Live attenuated influenza vaccine (LAIV) is contraindicated during pregnancy 2, 1
• Vaccination provides protection for both mother and infant through transplacental antibody transfer 2
• Infants born to vaccinated mothers have up to 72% risk reduction for laboratory-confirmed influenza hospitalization in the first few months of life 2

Treatment Guidelines

First-line Treatment

• Oseltamivir 75 mg twice daily for 5 days 1, 3
• Treatment should be initiated as soon as possible after symptom onset, ideally within 48 hours 2
• Do not delay treatment while awaiting laboratory confirmation 1

Alternative Treatment

• Zanamivir may be considered when there is suspected resistance to oseltamivir 1
• Consider respiratory complications from inhaled administration when prescribing zanamivir 1

Treatment Indications

• All pregnant women with suspected or confirmed influenza require treatment 1
• Pregnancy places women at increased risk for severe complications from influenza 2
• Early treatment reduces intensive care unit admissions and mortality 4

Prophylaxis Recommendations

• Oseltamivir prophylaxis (75 mg once daily) is recommended for 7-10 days after high-risk exposure 1
• May be considered for moderate-risk exposures but not for low-risk exposures 1
• Post-exposure prophylaxis should be considered in pandemic settings, particularly for non-vaccinated women 5

Safety Considerations

• Oseltamivir has been extensively studied in pregnancy with reassuring safety data 1, 6
• Limited transplacental transfer of oseltamivir and its active metabolite occurs 1, 5
• Observational data show reduction in severe outcomes without increased risk of adverse maternal, fetal, or neonatal outcomes 1
• The benefits of treating influenza in pregnancy substantially outweigh the theoretical risks of medication exposure 1

Management of Fever and Complications

• Use acetaminophen for fever reduction, as fever itself can cause adverse fetal outcomes 1
• Monitor closely for respiratory complications 1
• Consider hospitalization for pregnant women with severe symptoms or respiratory difficulty 1

Breastfeeding Considerations

• Breastfeeding is strongly recommended to protect infants against influenza viruses 2
• Breastfeeding activates innate antiviral mechanisms, specifically type 1 interferons 2
• Breast milk from vaccinated mothers contains higher levels of influenza-specific immunoglobulin A 2
• Breastfeeding should be encouraged even if the mother or infant has influenza 2
• If direct breastfeeding is not possible due to illness, mothers should pump and feed expressed milk 2

Common Pitfalls to Avoid

1. Delaying treatment while awaiting laboratory confirmation - this reduces effectiveness and increases risk of complications 1
2. Withholding vaccination due to concerns about safety - extensive evidence supports the safety of influenza vaccination during all trimesters 2, 7
3. Failing to recognize the increased risk of complications in pregnant women - pregnancy significantly increases risk for severe illness from influenza 2
4. Inadequate monitoring - pregnant women with influenza require close monitoring for respiratory complications 1
5. Underutilization of vaccination - despite recommendations, only about 35-50% of pregnant women receive influenza vaccination 2, 8

By following these evidence-based guidelines, clinicians can significantly reduce morbidity and mortality associated with influenza infection during pregnancy.