Vaccines during pregnancy: A significant proportion of pregnant women are not vaccinated against influenza and whooping cough

A recent weekly report published in the Centers for Disease Control and Prevention’s (CDC) Morbidity and Mortality Report (MMWR) revealed that only one in three pregnant women in the US receive two safe and effective vaccines recommended as part of the routine prenatal care, against influenza and pertussis (also known as whooping cough).1 The most commonly reported reasons for not receiving vaccinations were lack of knowledge about the recommendation and belief that they are ineffective for pertussis and influenza, respectively.1 Both infections are known to cause serious complications in pregnant women and are fatal among young infants.2,3 Based on these findings, the CDC strongly recommends the obstetricians and healthcare workers, who are on the front line of care for expectant mothers, to encourage maternal vaccinations through improved communication.1

Influenza and pertussis vaccines are recommended as part of the routine prenatal care by the Advisory Committee on Immunization Practices, in order to reduce the risk of infection and subsequent complications for pregnant women and their infants during the first few months of life.4 "Influenza and pertussis are serious infections that can be deadly for babies, especially those who are too young to be vaccinated directly," said Dr. Anne Schuchat, the principal deputy director of CDC, in a news briefing.5 The influenza vaccine can be taken at any time during pregnancy whilst the pertussis vaccine, referred to as Tdap, is recommended during the start of the third trimester of each pregnancy.4

Despite their lethality particularly to young infants, a recent study which included an internet panel survey conducted by the CDC reported low maternal vaccination coverage against both infections. The survey included responses from nearly 2,100 women aged 18 to 49 who were pregnant any time between August 2018 and April 2019.1 Results showed that 54.9% reported receiving the Tdap vaccine during pregnancy and 53.7% reported getting the influenza vaccine before or during pregnancy.1 Only 34.8% of pregnant women had reported receiving both the influenza and Tdap vaccines.1

Women whose healthcare providers offered or referred them for vaccination had the highest vaccination rates although approximately 30% of those who had received an offer or referral remained unvaccinated.1 Further analysis revealed that non-Hispanic black women had lower vaccination rates (for both vaccines) than women of other races and were less likely to report a healthcare provider offer or referral.1 The most commonly reported primary reason for not receiving the influenza vaccine was a belief that the vaccine was ineffective (17.6%). For Tdap, 37.9% reported lack of knowledge about the vaccination recommendation during each pregnancy.1

Analysis of surveillance data also showed that pregnant women accounted for 24-34% of reported influenza-associated hospitalizations (IAH) per influenza season from 2011 to 2018.1 The rate of IAH in infants younger than 6 months was 133 per 100,000 during the same period.1 From 2010 to 2017, infants less than 2 months of age accounted for 50.8% of infant pertussis hospitalizations and 69% of pertussis deaths reported by the National Notifiable Diseases Surveillance System.1

Based on these findings, the CDC urges the obstetricians and healthcare workers to initiate maternal vaccination discussions with expecting women early in pregnancy and tailoring information to individuals’ needs based on their vaccination-related concerns.1 The report also stated the importance of emphasizing well-documented safety and effectiveness of both vaccines.1 For instance, influenza vaccination reduces IAH by 40% for pregnant women and 72% for infants below 6 months of age.1 Tdap vaccination has 77.7% effectiveness in preventing pertussis and is 90.5% effective in preventing pertussis hospitalizations in infants aged younger than 2 months old.1 Enhanced communication may also improve pregnant women’s trust in the maternal vaccinations and reduce both their own and their newborns’ risk of having potentially serious health problems.1

  1. Lindley MC. Vital Signs: Burden and Prevention of Influenza and Pertussis Among Pregnant Women and Infants — United States. MMWR Morb Mortal Wkly Rep. 2019;68.
  2. CDC. Pregnant Women & Influenza (Flu) | CDC. Published October 16, 2019. Accessed October 17, 2019.
  3. CDC. Get the Whooping Cough Vaccine While You Are Pregnant. Centers for Disease Control and Prevention. Published September 5, 2019. Accessed October 17, 2019.
  4. CDC. Pregnancy Guidelines and Recommendations by Vaccine | CDC. Published April 19, 2019. Accessed October 17, 2019.
  5. CDC Press Release. Low Rates of Vaccination During Pregnancy Leave Moms, Babies Unprotected. Published October 8, 2019. Accessed October 17, 2019.