What is the management of measles in pregnancy?

Management of Measles in Pregnancy

Measles vaccine is contraindicated during pregnancy, but if a pregnant woman is exposed to measles, immune globulin (IG) should be administered within 6 days of exposure at a dose of 0.25 mL/kg body weight (maximum 15 mL) to prevent or modify disease. 1

Immediate Post-Exposure Management

For Susceptible Pregnant Women Exposed to Measles

• Administer IG within 6 days of exposure at 0.25 mL/kg body weight (maximum dose 15 mL) to prevent or modify measles infection 1
• IG is specifically indicated for pregnant women as a high-risk group for complications 1
• Measles-containing vaccine cannot be used for postexposure prophylaxis in pregnant women 1
• Even if IG is given, it may reduce but will not eliminate risk, and infants with congenital measles have been born to women who received IG shortly after exposure 1

Clinical Management of Active Measles Infection

Maternal Monitoring and Complications

• Pneumonia is the most serious and common complication, occurring in approximately 21% of pregnant women with measles compared to 9% in non-pregnant women 2
• Monitor closely for respiratory complications including pneumonitis, which was the most common serious complication in hospitalized pregnant women 3
• Watch for hepatitis, which occurred in over half of hospitalized pregnant cases 3
• Pregnant women with measles require hospitalization more frequently than non-pregnant adults, with 25% of adults with measles requiring ≥1 day of hospitalization 1

Pregnancy-Specific Risks

Measles during pregnancy significantly increases adverse outcomes: 1, 4

• Before 24 weeks gestation: High risk of spontaneous abortion or stillbirth, with 3 out of 4 cases in one series ending in pregnancy loss 4
• After 25 weeks gestation: Increased risk of premature labor and preterm delivery 4, 2, 3
• Low birth weight infants are more common 1
• Congenital measles can occur if infection happens near term, with rash appearing in the newborn within 10 days of birth 4, 5

Important Clinical Distinctions

• No specific congenital malformation syndrome has been demonstrated with measles infection during pregnancy, unlike rubella 1, 5
• The sudden onset and spontaneous nature of pregnancy termination in early gestational measles is characteristic 4
• Maternal mortality can occur, though it is uncommon in developed countries 3

Prevention Strategies

Pre-Pregnancy Counseling

• All women of childbearing age should have their measles immunity documented before pregnancy 1, 2
• Women without evidence of immunity should receive MMR vaccine, then avoid pregnancy for 4 weeks after vaccination 1
• Evidence of immunity includes: documented vaccination with 2 doses of live measles vaccine after first birthday, laboratory evidence of immunity, or physician-diagnosed measles 1

Vaccination Timing

• MMR vaccine should be administered immediately postpartum to susceptible women 1
• Pregnancy is an absolute contraindication to measles vaccination 1
• If a woman is inadvertently vaccinated during pregnancy or becomes pregnant within 4 weeks of vaccination, she should be counseled about theoretical risks, but this is not a reason to terminate pregnancy 1
• No cases of congenital abnormalities attributable to measles vaccine virus have been documented among infants born to women vaccinated during pregnancy 1

Household Contact Management

• Household contacts of pregnant women should be vaccinated with MMR to protect the pregnant woman from exposure 1
• MMR vaccine recipients do not transmit vaccine virus to contacts 1

Post-Exposure Follow-Up

• Any pregnant woman who receives IG for measles exposure should subsequently receive MMR vaccine postpartum, administered no earlier than 5-6 months after IG administration 1
• Women who develop measles during pregnancy should have their infants monitored for congenital measles if infection occurred near term 4, 5

Critical Pitfalls to Avoid

• Do not delay IG administration beyond 6 days post-exposure, as efficacy is time-dependent 1
• Do not assume women born before 1957 are immune; up to 9.3% may be susceptible 1, 6
• Do not use IG for routine postexposure prophylaxis of rubella in pregnancy, as it may create false reassurance while not preventing infection 1
• Do not withhold supportive care or treatment of secondary bacterial infections, as pneumonia is the leading cause of measles-related death 6