Mental imagery shapes vaccine decisions in pregnant women, study finds

The decision to get vaccinated during pregnancy is not purely rational. It is shaped, researchers have found, by the vivid pictures that form in a woman's mind when she contemplates the choice—images of protection or harm, of a healthy baby or a sick one in a hospital bed.

A new study led by researchers at the University of Western Australia and the University of Plymouth set out to measure something that had never been systematically examined before: the role of mental imagery in how pregnant women decide whether to receive vaccines against whooping cough, influenza, and COVID-19. The team recruited more than 400 pregnant women at King Edward Memorial Hospital in Perth, asking them to describe any mental images that came to mind when they thought about vaccination and disease risk. They also gathered their actual vaccination records to see which women ultimately got vaccinated, and when.

The results, published in Social Science & Medicine, revealed a striking pattern. Women who reported negative mental images about vaccines—scenarios of harm, side effects, or danger—were significantly more likely to express hesitancy toward whooping cough and influenza vaccines. This held true even when researchers controlled for women's general attitudes about government-recommended vaccines during pregnancy, suggesting that these vivid mental pictures captured something distinct and powerful in the decision-making process. The images were not simply reflections of what women already believed; they appeared to be active forces shaping their choices.

But positive imagery told a different story. Women who visualized protective mechanisms—antibodies crossing the umbilical cord, their babies being shielded from disease—were more likely to actually receive the whooping cough vaccine and to get it earlier in their pregnancies. The mental picture of protection seemed to translate into action in a way that abstract reassurance did not.

By the end of pregnancy, the actual uptake rates varied dramatically. Eighty-two percent of the women in the study received the whooping cough vaccine. Sixty percent got the influenza vaccine. Only 7.2 percent received the COVID-19 vaccine. These numbers reflect not just individual hesitation but a landscape of shifting confidence in different vaccines during a uniquely vulnerable time.

Dr. Julie Ji, who led the research, emphasized that pregnancy is a period when health decisions carry unusual emotional weight. "Vivid emotional mental scenes that pop to mind when someone is thinking about vaccination are not just incidental," she said. "They may be meaningfully linked to how people feel about vaccines, and in some cases, whether and when they get vaccinated." The finding suggests that the images in a woman's mind—whether they arrive unbidden or are planted by health messaging—matter as much as the facts themselves.

Professor Katie Attwell, who directs the vaccine policy research lab at UWA, saw in these findings a practical opportunity. At a moment when vaccine hesitancy poses real threats to public health, understanding the power of mental imagery opens a new avenue for intervention. "Now that we understand the importance of these mental images, we can support health professionals and government campaigns to be more conscious of what visual seeds they might be sowing," she said. The research team is now investigating how to deliberately harness positive mental imagery to support informed decision-making during pregnancy—not through manipulation, but through a clearer understanding of how the mind actually works when stakes are high and uncertainty is real.