What is true about maternal antibodies?

Maternal antibodies are classified as natural passive acquired immunity because they are transferred from the mother to the infant through placenta during pregnancy and through breast milk after birth. This type of immunity provides the newborn with immediate, though temporary, protection against certain infections without the infant having to actively produce antibodies on its own.

Natural passive immunity is distinct from active immunity, where the body generates its own antibodies in response to infections or vaccinations. While maternal antibodies offer crucial early protection as the infant's immune system develops, they do not provide permanent immunity; instead, their levels decrease over time. Therefore, the classification of maternal antibodies as natural passive acquired immunity highlights their role in protecting infants in their early months, relying on the mother's immune experience without the infant having participated in an immune response.