Vaccination plays an important role for the health of mother and the baby. There is a benefit for women to be immunized to reduce their chances of morbidity and mortality from vaccine-preventable diseases. Before administering a vaccine to a pregnant woman, the prenatal health care provider must know the immunogenic material in the vaccine. Live, attenuated virus vaccines, such as the MMR vaccine or the nasally delivered influenza vaccine, are not recommended in pregnancy. In contrast, vaccines that contain nonviable antigens, virus-like particles, or noninfectious yet immunogenic components of bacteria, such as the tetanus toxoid, reduced diphtheria toxoid and acellular pertussis (Tdap) vaccine and the injectable influenza vaccine, are considered safe during pregnancy.
Health care providers and patients should be aware that the reassuring safety data for use of the aforementioned vaccines in pregnancy are compelling, and there is no link to vaccine administration and miscarriage. An added benefit to immunizing during pregnancy is the potential for disease prevention in newborns by way of passive antibody transfer to the fetus. Hence, offering pregnant patients influenza and Tdap vaccines is an avenue to protect newborn infants at a critically vulnerable time and before neonates can be vaccinated. Patients who decline vaccinations indicated during pregnancy should be offered and given postpartum immunization.
Influenza is more likely to cause severe illness in pregnant women than in women who are not pregnant. Changes in the immune system, heart, and lungs during pregnancy make pregnant women more prone to severe illness from influenza as well as hospitalizations and even death. Pregnant women with influenza also have a greater chance for serious problems for their unborn babies, including premature labor and delivery. Because vaccinating against influenza before the season begins is critical, and because predicting exactly when the season will begin is impossible, routine influenza vaccination is recommended for all women who are or will be pregnant (in any trimester) during influenza season, which in the United States is usually early October through late March. Pregnant women should receive inactivated influenza vaccine. Neither CDC nor ACOG recommend one type of flu vaccine. All influenza vaccines available are recommended for use in pregnant women, with the exception of the live intranasal vaccine, which is contraindicated for pregnant women.
The influenza vaccine is safe for pregnant women and their unborn children as well as postpartum and breast feeding women and can be given during any trimester. Immunizing pregnant and postpartum women against seasonal influenza can protect the mother and may help her baby by preventing the spread of the flu from mother to child following delivery. The seasonal flu vaccine has been given safely to millions of pregnant women over the past 45 years. The flu shot has been recommended by the American College of Obstetricians and Gynecologists and the U.S. Centers for Disease Control and Prevention for pregnant women for many years.
For more information, read ACOG’s Committee Opinion 608 "Influenza Vaccination During Pregnancy," published September 2014.
The overwhelming majority of morbidity and mortality attributable to pertussis (whooping cough) infection occurs in infants who are less than or equal to 3 months of age, who are too young to begin their own vaccine series against pertussis (whooping cough). Vaccinating pregnant women with Tdap stimulates the development of maternal anti-pertussis antibodies, which pass through the placenta, providing the newborn with protection against pertussis in early life, and protects the mother from pertussis around the time of delivery, making her less likely to become infected and transmit pertussis to her infant. The Advisory Committee on Immunization Practices guidelines recommend that health care personnel administer a dose of Tdap during each pregnancy, irrespective of the patient’s prior history of receiving Tdap. To maximize the maternal antibody response, passive antibody transfer and levels in the newborn, optimal timing for Tdap administration is between 27 weeks and 36 weeks of gestation, although Tdap may be given at any time during pregnancy.
For women who previously have not received Tdap, if Tdap was not administered during pregnancy it should be administered immediately postpartum to the mother in order to reduce the risk of transmission to the newborn. It is also safe to administer Tdap to breastfeeding women.
It is recommended that all adolescents and adults who have or who anticipate having close contact with an infant younger than 12 months (eg, siblings, parents, grandparents, child care providers, and health care providers) who previously have not received Tdap should receive a single dose of Tdap to protect against pertussis and reduce the likelihood of transmission. Ideally, these adolescents and adults should receive Tdap at least 2 weeks before they have close contact with the infant.
For more information read ACOG's most recent guidelines on Tdap vaccination in pregnancy, Committee Opinion 566, "Update on Immunization and Pregnancy: Tetanus, Diphtheria, and Pertussis Vaccination," published June 2013.