The six groups -- including the American Academy of Pediatrics (AAP), the American College of Physicians (ACP) and the Society for Maternal-Fetal Medicine (SMFM) -- as well as a pregnant woman filed the lawsuit in the U.S. District Court for the District of Massachusetts.

Pediatricians say the parents of their patients are anxious and confused about vaccine safety and access as federal immunization policies shift under Health and Human Services Secretary Robert F. Kennedy Jr.

The lawsuit argues that the HHS secretary’s withdrawal of public vaccine advice reduces access to vaccines for some people.