The evidence behind what we say.
51& cites every public claim we make. Below is the evidence, with links to the original research. If you ever find something here that needs correcting, tell us at hello@51and.com and we’ll fix it.
- 1
Women are 51% of the population.
U.S. Census Bureau, population estimates. Women are just over half of the U.S. population and a slightly larger share of adults, since women live longer on average.
- 2
51% of women report a negative healthcare experience; 32% skip or delay care because of cost.
Gallup, in partnership with Pivotal, “More than half of U.S. women report negative healthcare experiences” (September 2026). 51% of women reported at least one of four negative healthcare experiences in the past five years (vs. 39% of men), and 32% skipped or delayed needed care because of cost in the past year (vs. 25% of men).
- 3
Women make 80% of healthcare decisions.
A widely cited estimate of women’s role as the primary healthcare decision-maker for their households, used across the industry.
A note on this one, in the spirit of full transparency: the 80% figure is repeated very widely but is difficult to trace to a single primary study, and is often attributed loosely to the U.S. Department of Labor. We treat it as a well-established industry estimate rather than a precise measurement. The institutional sources below use and support it, and the broader point—that women drive the majority of health decisions for their families—is well documented.
- 4
We're diagnosed later, and dismissed more often.
Westergaard et al., “Population-wide analysis of differences in disease progression patterns in men and women,” Nature Communications (2019). A University of Copenhagen study of the entire Danish population (roughly 6.9 million people over 21 years) found that women are diagnosed later than men across a wide range of diseases.
- 5
We pay more out of our own pockets.
Deloitte analysis (September 2023): employed women have as much as $15.4 billion more in out-of-pocket medical expenses a year than men, even when maternity-related costs are excluded.
Last reviewed October 2026.