A 28-year-old pregnant woman at 6 months gestation attends the antenatal clinic in Delhi. She has no documented history of vaccination and is seronegative for rubella. The clinic nurse is about to administer rubella vaccine. What is the most appropriate immediate action?

Explanation

## Clinical Context Rubella vaccination in pregnancy is a critical safety issue. The patient is seronegative (non-immune) but is currently pregnant — a live attenuated vaccine cannot be given during pregnancy. ## Key Point: **Live attenuated vaccines (MMR, varicella, rotavirus, yellow fever) are contraindicated in pregnancy** due to theoretical risk of vaccine-strain infection of the fetus, even though actual cases of congenital vaccine-strain disease are extremely rare. ## Management Strategy 1. **Defer vaccination** until after delivery (postpartum period is safe) 2. **Counsel on breastfeeding**: Rubella vaccine given postpartum is safe even while breastfeeding — maternal antibodies do not neutralize the vaccine virus in the infant's GI tract 3. **Document seronegative status** for future reference 4. **Advise on natural infection risk** during remaining pregnancy ## High-Yield: **Postpartum vaccination is the standard of care** for seronegative pregnant women. This protects the woman and future pregnancies (passive immunity wanes over time, so vaccination now prevents congenital rubella in the next pregnancy). ## Clinical Pearl: Breastfeeding mothers can safely receive live vaccines postpartum — the vaccine virus is not transmitted through breast milk in clinically significant amounts, and any maternal antibodies in milk do not prevent infant immunization if needed later.