Targeting Uncertainty: Why Pregnancy May Be the Best Time to Build Vaccine Confidence

The doctor is injecting a vaccination into the arm of a little girl.

(Adobe Stock 170524806 by pingpao)

Vaccination remains a cornerstone of infection prevention, yet many parents in the US choose to delay or refuse vaccines recommended for their child from birth to 18 months. Research exploring the optimal moments to engage families on vaccination decisions is critical, particularly for infection prevention and control (IPC) and public health professionals looking to support higher immunization rates and protect vulnerable pediatric populations.

A new study published in JAMA Network Open examined this issue by conducting two concurrent national cross-sectional surveys in April 2024. Researchers surveyed 174 pregnant participants and 1,765 parents of children aged 0 to 5 years, collecting data on their intentions or actual behaviors regarding vaccinations for their children. Participants were drawn from a nationally representative panel of US adults, with demographic characteristics broadly matching the US population.

Among pregnant participants, 37.6% were experiencing their first pregnancy (nulliparous). Approximately half of both pregnant participants and parents had a bachelor’s degree or higher. Most respondents were currently married and lived in urban areas.

“Participants who were pregnant were asked about vaccination intention for their child after birth with the question: ‘Will your child receive any vaccinations after birth?’ (with response options of ‘yes,’ ‘no,’ and ‘I don’t know’),” the authors explained. “Those responding yes were asked, ‘Do you plan to refuse or choose not to get 1 or more recommended vaccines (including seasonal flu or COVID-19 vaccines) for your child after birth?’ followed by, ‘Do you plan to delay or space out ANY recommended vaccines (including seasonal flu or COVID-19 vaccines) for your child after birth?’ (responses for both questions were ‘yes,’ ‘no,’ or ‘I don’t know’).”

The study found that overall, intentions to accept all recommended childhood vaccines were fairly consistent between pregnant participants and parents of young children. However, notable differences emerged around outright refusal or uncertainty. The proportion of those intending to refuse or refusing some or all vaccines (without delays) was lowest among nulliparous pregnant participants at just 4% (5 of 68), but highest among parents at 33% (391 of 1,765). Meanwhile, uncertainty about vaccination was most pronounced among pregnant individuals experiencing their first pregnancy—48% (31 of 68) were undecided about childhood vaccinations. This uncertainty dropped substantially among parents, with only 4% (78 of 1,765) reporting they were undecided.

“Given the high decisional uncertainty during pregnancy about vaccinating children after birth, there may be value in intervening during pregnancy to proactively support families with childhood vaccination decisions,” the authors wrote.

These findings highlight a critical window of opportunity during pregnancy, especially for first-time parents, when proactive education and engagement could help shape vaccination decisions. Given that uncertainty is highest during this period, tailored interventions by health care providers—including obstetric teams, family physicians, and IPC educators—may be particularly impactful.

“Vaccines are a foundational element of the health and safety of all children,” Isis Lamphier, MPH, MHA, CIC, AL-CIP, the manager of infection prevention at Moffitt Cancer Center, and who was not involved in the study. “Due to decreasing vaccine adherence to the immunization schedule in children, the US has seen a reemergence of vaccine-preventable diseases in children. These vaccine-preventable diseases can be detrimental to children and can spread rapidly due to the underdeveloped immune system of children.”

Lamphier, a member of Infection Control Today®’s Editorial Advisory Board, is concerned about the future. “It is critical for infection preventionists (IPs) to continue to advocate for vaccines, including reaching expectant mothers. Mothers who forgo following immunization schedules for their children not only impact the health and safety of their own children, but also that of other children, including those who are receiving immunizations or who will receive them once they are old enough. We do not want to move backwards with the progress we have made to prevent these diseases in the US.”

The study’s strengths include its national scope and the application of geodemographically calibrated weights to better reflect the US population. However, it also faced limitations, such as being unable to directly confirm whether vaccination intentions during pregnancy aligned with later behaviors. Additionally, prior experiences with vaccinating older children could have influenced responses, and small sample counts in some subgroups may have affected the stability of certain estimates.

For IPC professionals, these insights reinforce the importance of engaging families early, potentially even before a child’s birth, to build confidence in vaccines that prevent severe infectious diseases. Future longitudinal studies could further clarify how decisions evolve from pregnancy into parenthood, and how proactive interventions during pregnancy might sustain higher vaccine uptake and better protect pediatric populations from preventable infections.

As Jill Holdsworth, MS, CIC, FAPIC, NREMT, CRCST, CHL, an IP in Atlanta, Georgia, reminds IPC personnel, “With growing uncertainty around vaccination, we, as IPs, have an opportunity to make an impact in expectant mothers’ decisions through education and awareness early in their pregnancy.”