context: For many of us, becoming an adult means leaving behind the trappings of our youth, but immunizations are not necessarily one of them. Many of the vaccinations we had as children need to be repeated as adults to maintain proper immunity. And just as adulthood brings a new set of responsibilities, being an adult can also require a new set of immunizations. Many of the vaccines we received as children to create immunities to infectious diseases last a lifetime, but not all of them. For example, tetanus and diphtheria vaccines need to be updated with a new vaccine and then with booster shots every 10 years to maintain immunity. There are other reasons why adult immunizations may be necessary: Some adults never received immunizations as children. Vaccine recommendations and vaccines change over the years. Certain vaccines may not have been available when some adults were children. Immunity can begin to fade over time. As we age, we become more susceptible to serious disease caused by common infections like the flu. As an adult we may work in the health care field or other profession that puts us at risk for contact with infectious diseases. There have been several updates in adult vaccine recommendations since the last set of guidelines were released. One of the most notable: the Advisory Committee on Immunization Practices ( ACIP) recommends that the human papillomavirus ( HPV) vaccine be given to all adult females through the age of 26. Guidelines for males are similar, calling for vaccinations of males aged 13 through 21 years who were not been previously vaccinated. Vaccination is also recommended for males through age 26 who have sex with other men and for those whose immune system may be compromised. Other significant changes include: The ACIP now suggests that adults without evidence of prior immunity to chickenpox receive the varicella vaccine. Special consideration should be given to: Those at high risk for infection or transmission, such as health care workers and teachers. Those who are in close contact with people at high risk of infection. Family and others who come in contact with people with compromised immune systems. Shingles, the adult form of chickenpox, can be a very painful and debilitating disease. People aged 60 years and over and people without without evidence of immunity who are known to be at risk of exposure should be vaccinated against shingles. The ACIP also recommends one or more doses of the measles, mumps, rubella vaccine ( MMR) be administered to adults in certain age groups and with certain risk factors. Adults born before 1957 can be considered immune to measles and mumps. Hepatitis B vaccine is recommended for adults seeking protection from hepatitis B exposure. Any adult working in high-risk environments like STD clinics or drug rehab centers, should be vaccinated for Hepatitis B. Health care workers, public safety workers, household contacts, and sexual partners of persons with chronic hepatitis B should also receive the hepatitis B vaccine. If you are pregnant or planning to become pregnant, it is important that you make sure your adult immunizations are current. A child's first set of immunities is often passed on from the mother, and more importantly, contracting certain infectious diseases -- such as rubella -- while pregnant greatly increases a child's risk of birth defects. The benefits of vaccinating pregnant women usually outweighs the risks of the vaccine, says the CDC. Risks to a developing fetus from a vaccine are largely theoretical, while risks to a fetus from an infectious disease contracted by the mother are well documented. All women who are pregnant need to talk with their doctor about getting a flu shot and about getting the Tdap vaccine. The Tdap vaccine provides protection against tetanus, diphtheria, and pertussis and should be given during the third trimester of each pregnancy. If you are pregnant or trying to become pregnant, talk to your health care provider before being vaccinated with a live virus vaccine, such as chickenpox, measles, or the LAIV flu vaccine. If possible, avoid live virus vaccinations during pregnancy or right before pregnancy since live virus vaccines can increase the risk of transmitting the disease to the fetus. If you're considering becoming pregnant and need a live virus vaccine, wait at least four weeks after vaccination before trying to get pregnant.