Psychotherapist Frieda Birnbaum, of Saddle River, NJ, garnered international media attention—and criticism—when, at age 60, she became the oldest American woman to give birth to twins. The backlash surprised her but inspired her write a memoir, "Life Begins at 60: A New View on Motherhood, Marriage, and Reinventing Ourselves." Here, she explained to Sarah Klein why becoming a late-in-life mom was the right choice for her.

"If you want more children, why don't you wait, and you will have grandchildren?" I'll never forget my eldest son, Jaeson, speaking those words to me. I was in my early 50s and had just told him I was going to try to become pregnant. At first, I wasn't sure what to do: I didn't want to upset him, and I wanted to make sure my decision was something my whole family would be OK with. But I was determined to have another child. (Looking to take back control of your health? Prevention magazine has smart answers—get 2 FREE gifts when you subscribe today.)

I loved being a mother to Jaeson and his sister Alana, who I had when I was in my late 20s and early 30s, but they grew up so fast. Now I was desperate to be a mom again; I even got excited seeing the word "adopt" on an "Adopt a Highway" sign. But Jaeson, who was a grown man in his 30s, felt it was his turn to have children, not mine. His disdain for my plans really made me question them, but it didn't dissuade me: Up until that point, I had spent my whole life doing what made other people happy, which I think a lot of women do. It was my turn to do what I wanted, and my husband was on board. We decided to try for another child.

Although I was in good health and hadn't quite reached menopause yet, the odds of getting pregnant naturally after age 50 are slim, so we decided to try in vitro fertilization (IVF). I got pregnant, but 3 months later I miscarried. I was crushed, but it wasn't a total shock: After age 45, the chances of miscarrying go way up. (Read this woman’s story about the devastating reason why she’ll never have another baby.) Two years later, we gave it another shot, and at 53 I had my third child, Ari.

Challenging norms 
My husband and I were thrilled, but there were times when I felt downright self-conscious, even embarrassed, about being older than the young moms who had children the same age as Ari. But after a while I realized that no one seemed to know, or maybe they just didn't care.

When Ari was a toddler, I decided I wanted him to have a sibling closer to his age. I still felt as young and energetic as ever, but this time I hit a snag: I was 56, and the fertility specialist I consulted told me the age cutoff for IVF at his clinic was 55. (Many others draw the line at 42 or 45; here are 13 things you need to know about IVF.)

Around the same time, I read an article about how fertility clinics in some countries don't have the same age limits—and that the procedure is much less costly overseas. I showed the article to my husband. "I am too old," I said, "but the price is right." "No," he replied. "You are not too old. You're young for your years, so we'll try it." (Check out these 7 ways doctors pre-judge you—and how it hurts your care.)

We spent a few years researching our options, and eventually flew to Africa for the procedure. Although the trip had its hiccups, including a rough safari and an even rougher helicopter ride, we came home elated: The IVF treatment had worked, and I was pregnant—with twins!—at 60 years old.

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Even though I was elated, I was still nervous about what others might think. I didn't get that big during my pregnancy, so I was able to disguise it with suit jackets and scarves. I remember being in the supermarket toward the end of my pregnancy, and I needed help lifting a gallon of milk into my cart. Initially, I told the supermarket employee I had a bad back; I didn't want to tell her the real reason. But then I decided to forge ahead and revealed that I was pregnant, then watched her face to see if she was going to fall over out of shock. She was barely fazed, and I stopped feeling like some kind of freak.

When I was getting ready to deliver, the chief of staff at the hospital asked if I would feel comfortable revealing my age and sharing my story publicly, since he had never helped a woman of my age deliver a baby (or in my case, babies). There are only about 740 births a year to mothers over 50 in the whole country, compared with over 2 million to moms between 25 and 34. And I was about to become the oldest American woman to give birth to twins.

In the past, I had often lied about my age, saying I was 10 years younger than I was. So I was a bit hesitant to broadcast the truth now. "You can make a difference to other women who are contemplating having children but might feel uncomfortable about their age," the chief of staff assured me. I agreed.

Going public

The birth of my twins was actually much easier than my other deliveries, and both babies were deemed healthy right away. But then the chaos started: The hospital parking lot was crammed with reporters and camera teams from every major media outlet. There was nowhere for my own family to park because the news trucks were taking up all the spots.

After the stories came out, I was surprised by just how shocked the world was by my age. I didn't feel old. And there's such a double standard: Men who have children later in life are considered virile, while women face discrimination and intense questioning like I did. Rod Stewart had a child at the same age I did, and no one mentioned a thing about his age.

People kept asking me why I decided to get pregnant at 60. They reminded me that I'll be in my late 70s when my twins go to college and as old as my 90s when they have their own babies. People called me selfish and claimed I did it for the fame or money or youthfulness. Trust me, you don't feel or look younger when you're running after kids, and I didn't make any money off of my children.

Most of them didn't seem to accept that my decision was really well thought out. I had looked at my own health and vitality and knew I was really up for it. I knew I had longevity on my side: My father lived into his 90s, and my mother close to that. Both passed away from accidents, so I suspect they could have lived even longer.

While much of the attention I got was critical, I also received tons of phone calls from women around the world thanking me and telling me I gave them permission to feel youthful. My babies are now 9, and the calls still come in. Women feel validated by someone like me who says it's OK to be who you are and that you can still be vital at "middle age." I think we should call it "peak age" instead, since it really is when you're at your best.

Today I have three grandchildren 8 and under, and they all love to come over and play with my twins. I still feel excited for the future—not just for them, but for me, too, since I believe I have many exciting decades in front of me. Recently, as all the kids were playing in our back yard, Jaeson, now in his early 40s, turned to me and said he's happy about my decision now that he sees his children and the twins playing together. Having babies when you're 60 might be unusual, but that doesn't mean it's negative. It has reenergized our entire family.

This article originally appeared on Prevention.com.