Should an 18-week pregnant woman with no medical history start Paxlovid (nirmatrelvir/ritonavir) for COVID-19 treatment?

Management of COVID-19 in Pregnant Women at 18 Weeks Gestation

Paxlovid (nirmatrelvir/ritonavir) is not routinely recommended for an 18-week pregnant woman with no medical history who has COVID-19, as the benefits do not clearly outweigh the potential unknown risks in this specific scenario.

Decision-Making Framework for Paxlovid in Pregnancy

Risk Assessment

• Pregnancy itself increases the risk of morbidity and mortality from COVID-19 infection due to:
  • Relatively immunocompromised state 1
  • Alterations in pulmonary function 1
  • Hypercoagulable state 1

Evidence on Paxlovid in Pregnancy

• Limited data exists on Paxlovid use during pregnancy as pregnant women were excluded from clinical trials 1
• Recent small study (2023) showed:
  • Shorter duration of COVID-19 symptoms in Paxlovid-treated pregnant women (10.10 days vs 15.59 days) 2
  • No severe adverse events reported 2
  • However, higher cesarean delivery rates (76.92% vs 42.86%) and potentially more small-for-gestational-age infants (23.08% vs 3.57%) 2
• Another study found that 91.7% of pregnant women taking Paxlovid experienced dysgeusia and 50% had COVID rebound 3

Risk-Benefit Analysis

• For pregnant women without additional risk factors:
  • The most recent evidence shows no significant difference in time to sustained alleviation of COVID-19 symptoms between Paxlovid and placebo in standard-risk patients 4
  • "Unknown risk" is the most common reason pregnant women decline Paxlovid 3

Current Guidelines

• While some countries have prioritized pregnant women for COVID-19 vaccination, there is insufficient guidance specifically addressing Paxlovid use in pregnancy 1
• The Society for Maternal-Fetal Medicine acknowledges the lack of pregnancy-specific data for COVID-19 therapeutics 1
• Management should focus on appropriate monitoring and thromboprophylaxis when indicated 5

Recommended Management Approach

1. Monitoring and Supportive Care

   • Self-monitoring for symptoms with regular virtual check-ins with healthcare provider 5
   • Prompt reporting of any new or worsening symptoms 5
   • Rest, hydration, and antipyretics as needed

2. Thromboprophylaxis Considerations

   • Not routinely indicated for mild COVID-19 in outpatient setting
   • Consider weight-adjusted LMWH if hospitalization becomes necessary 1, 5
   • Monitor for signs of thrombosis given pregnancy's inherent hypercoagulable state 1

3. Fetal Monitoring

   • Arrange fetal growth surveillance 14 days after symptom resolution 5
   • No evidence of increased risk of miscarriage or teratogenicity from COVID-19 infection 5

4. When to Consider Escalation of Care

   • Persistent fever >39°C despite antipyretics
   • Respiratory distress or oxygen saturation <95%
   • Inability to maintain oral hydration
   • Signs of severe disease requiring hospitalization

Important Caveats

• The absence of data is not equivalent to the presence of harm, but caution is warranted 1
• If the patient develops severe COVID-19 or has additional risk factors (diabetes, obesity, advanced maternal age), the risk-benefit assessment may change
• Vertical transmission of COVID-19 is considered "probable" but rare 5
• Continuous monitoring of emerging evidence is essential as more data becomes available on Paxlovid use in pregnancy

In this specific case of an 18-week pregnant woman with no medical history, the current evidence does not strongly support initiating Paxlovid, as the benefits have not been clearly demonstrated to outweigh the potential unknown risks in pregnancy.