The new recommendation for pregnant women is contained in the 2013 version of the U.S. adult immunizationschedule, updated yearly by the CDC's vaccine advisory panel.
However, in the U.S., the current immunizationschedule for this disease begins for high-risk children at two years of age and is recommended for all at age 11.
After a lengthy and thorough review of the evidence, the IOM issued a report last week that found that the current childhood immunizationschedule in the United States is safe.
The phase 3 trial actually compared smoking cessation outcomes for vaccination and placebo for several months after the vaccination schedule, whereas the current study focused on the period just after immunization.