As I was writing Previvors: Facing the Breast Cancer Gene and Making Life-Changing Decisions, I realized how blessed women are today. Generations ago, people were blindsided by breast cancer. They had no warning if and when it was going to strike. But then along came this whole concept of Previvors: People who have not had cancer but have a predisposition to develop it because of certain risk factors. Today, previvors can take steps to outwit the disease by learning their risk and the options they have to protect themselves. In other words, while breast cancer is still a horrific, sometimes fatal illness, women like those featured in Previvors are actually aiming to fight it before they're diagnosed.

Since knowing your risk is crucial if you want to fight your fate, it's important to learn the common risk factors for breast cancer. Some, like your age, getting your first period early, and a high breast density, you can't control. Others like being overweight and consuming too much alcohol, you can.

And then there's the rapidly evolving world of genetics. Researchers have found that certain changes in a person's DNA can affect breast cancer risk. The most predominant link you've probably heard of is often called “the breast cancer gene.” Actually, there are two tumor suppressor genes called BRCA1 and BRCA2 (pronounced brak-uh). Their role is to control the growth of cells in the breasts and ovaries (or essentially to prevent cancer from forming). We are all born with two copies of each—one from our mothers and one from our fathers. If either copy of BRCA1 or BRCA2 is not working properly—what's known as a genetic mutation—that person's odds of getting cancer compound significantly: up to an 87% chance of developing breast cancer during their lifetime and up to a 44% chance of developing ovarian cancer during their lifetime. Experts can't yet tell a person where exactly they lie on the spectrum—say, a 35% chance of developing breast cancer—though they predict they will be able to in the future. So for now, they offer the vague “up to 87% and 44% odds.”

Having a BRCA mutation does not guarantee that a person will develop cancer, just as not having it doesn't mean that they won't. What it does mean is that they inherited the gene from either their mother or their father, and that their children and siblings each have a 50% chance of having it too. An important note: Men are just as likely to have a BRCA mutation as women are. While it increases a man's own odds of breast cancer, prostate cancer, and melanoma, he can also pass it on to his daughters and granddaughters which, in turn, greatly affect their risk.

How do you know if you're at risk for having a BRCA mutation? First, take a look at your family history on your mother's and father's side. If there are several members on the same side who have battled cancer, or if there's any male breast cancer or ovarian cancer in your family, you might want to consider seeing a genetic counselor. Facing your risk can be overwhelming and confusing, and trying to do so on your own might lead you to making potentially life-changing decisions based on information you don't fully understand. A genetic counselor will help determine your risk and its implications, and will guide you through your various options.

Of course, plenty of women without BRCA mutations develop cancer. The key is to take the initiative and talk to an expert about your individual risk. If a woman discovers that she has a high risk for breast cancer because of a BRCA mutation, family history, or other factors, the good news is that she has so many more options than women did years ago. Surveillance methods catch more cancers at earlier stages. There are pills you can take that will lower your risk up to 50%. And even prophylactic mastectomies have improved to the point that a woman can achieve results that look completely natural.

Bottom line: We no longer have to sit around and wait for breast cancer to strike. We have choices, and it's time we stood up to breast cancer and turn our fear into empowerment. After all, knowledge is power. And learning this vital information gives us control over a disease that has been winning for way too long.

Dina Roth Port served as an assistant health editor at Glamour and as an editor at Parenting. Now a full-time freelance writer living in Boca Raton, her work has appeared in publications such as Glamour, Self, Parenting, Cosmopolitan, Natural Health, Fitness, Martha Stewart Weddings, and Prevention. Her book, Previvors: Facing the Breast Cancer Gene and Making Life-Changing Decisions, is available October 2010. For more information, visit www.dinarothport.com.