If you happen to be one of the 60,000 Canadians every year who has a cardiac arrest outside a hospital, you should know that among the many factors that will determine if you live or die will be whether you have breasts.
Put another way: if you have breasts, bystanders will be less likely to administer cardiopulmonary resuscitation, or CPR, a series of lifesaving chest compressions that can double or even triple your chance of survival.
A study published in 2018, which looked at data from almost 20,000 out-of-hospital cardiac arrests in the U.S., found that, in public settings – such as on a roadway, in a public building, or in a park – only 39 per cent of women received CPR from bystanders compared to 45 per cent of men.
Interestingly, in private settings, like a family home, there was no difference.
This is important, because the researchers also found that getting bystander CPR was significantly associated with surviving long enough to be discharged from the hospital, assuming the person makes it there. And so, not surprisingly, men were more likely to survive than women.
The researchers did not offer an explanation for the disparity. But other research suggests that the issue is breasts.
In 2024, for instance, St. John’s Ambulance in Britain conducted a survey on 1,000 people. Among the 500 who identified as male, a third said they’d be less likely to perform CPR on a female. (Thirteen per cent of women also said they’d hesitate.) Reluctant men said they were concerned they might be accused of sexual assault.
The idea of using an automated external defibrillator (AED) made things worse. CPR can be done through a shirt, but using an AED involves placing pads on bare skin in the chest area, which means taking off a woman’s clothing – and cutting off her bra. Even though using an AED within the first three minutes can increase odds of survival by as much as 70 per cent, almost half of men said they probably wouldn’t do it.
The survey led to a campaign featuring a bra emblazoned with the words, “It’s okay to save my life.”
Opinion: We need to create a culture of life savers to address cardiac arrest
But getting over reluctance is only one of the problems. Performing CPR effectively on a woman’s body when you’ve never trained on one is another.
Most people who learn CPR in Canada train on a head-and-upper-body manikin, some of which are able to measure things like the speed and depth of compressions. According to a 2025 study from Spain, even second-year nursing students performed worse on female training manikins than male ones. They were slower to start, less likely to place their hands correctly, and less likely to perform compressions with an adequate depth. That improved after training on female manikins. The anatomical design of the manikins used in basic lifesaving training, the authors write, “influences the technical, emotional and attitudinal performance of students.”
It makes sense. The lower half of the sternum is the focus of the CPR intervention. Breasts make a difference, even on manikins. Students are taught to use the heel of their hand and keep fingers raised, but with female anatomy, fingers will necessarily be touching a breast. In real life, the differences could be even greater. The spot on the sternum might be blocked by breasts pressed together in a bra. Large breasts may move during compressions. Even the way we identify where to press – equidistant between the nipples – may not always be correct on real bodies.
Despite that, almost all lifesaving training is done on flat-chested training torsos: 95 per cent of all CPR manikins on the market worldwide in 2024 were male-type. So you can be sure that most of the laypeople who might come to your aid on a street corner, even if they know CPR, will have never practiced on a manikin with breasts.
It’s time to change that. Training on breasted manikins should be mandatory.
Within the last few years, more breasted options have become available. One leading manikin maker allows you to swap out a flat chest for one with breasts. Some breasts snap onto existing flat-chested manikins. Or you can just choose female. There are Canadian training organizations already using some of these, but they couldn’t say to what extent. No one seemed to have a policy mandating them, the way many mandate training on infant manikins.
Change can be slow as new standards filter down. Last year, the American Heart Association came out saying you don’t have to remove a bra to use an AED, so long as you place the defibrillator pads correctly. The Lifesaving Society’s revised first-aid manual, out this summer, will discuss that option, says lead spokesperson Stephanie Bakalar.
Still, it is a good idea to be comfortable cutting off a bra, she says, as it’s fast. “This person is unconscious. They are unresponsive. They will not survive without medical intervention.”
A final tip from the Canadian Red Cross: People worried about being misconstrued as they perform CPR should tell other bystanders what they are doing. Count compressions out loud, so that everyone knows this is a lifesaving intervention. Delays matter. Four minutes without oxygen can cause brain damage, says Chris Schmied, of St. John’s Ambulance.
“Get over it,” he says. “If it were somebody you knew and loved, what would you want somebody else doing?”