I recently read that women are writing a new playbook of power in order to create the world they want to live in. Yes, we have been finding a louder voice lately and it’s a wonderful chorus. The problem is that in order to write a “new playbook of power” more of us need to break into traditional roles of power—like CEOs of hospitals and health systems.

The latest statistics tell us that although women make up 80 percent of the health care workforce—and now represent half of all medical students—only 8 percent of us are CEOs of top 100 hospitals. And only one of us is the CEO of a Fortune 500 health care company.

What’s holding us back?

1. According to Harvard T.H. Chan School of Public Health, a major obstacle in women gaining top leadership roles is that leaders, in this case male leaders, often choose successors that are most similar to them. Since women don’t “look” or “act” like men, we don’t match the image most decision makers either consciously or subconsciously see as top leaders, thus lessening our chances of being promoted to top leadership roles.

2. When women are promoted to executive positions they are typically promoted to staff or support positions such as human resources, communications or legal and not the top strategic leadership roles that lead to the CEO position. In addition, when women try to assert themselves in these leadership roles they often experience backlash against their authority and competence.

3. As women we often do not advocate for ourselves. We temper our aspirations believing leadership is not possible for us. Former Supreme Court Justice Sandra Day O’Connor was recently quoted in a piece for thecut.com as saying,

“The acquisition of power requires that one aspire to power, that one believe it is possible. As women then achieve power and exercise it well, the barriers fall. That’s why I’m optimistic. As society sees what women can do, as women see what women can do, there will be even more women out there doing things.”