Transcript for Going Through Breast Reduction Surgery as a Teenager

? We all know some young girls dream of being bustier, but for a growing number of girls, some as young as 12, an over ample booze bosom can lead to pain and. Some consider it a curse. Are they old enough to weigh the Po ten shlt risks down the line? Like most teenager girls Mackenzie loves to shop. I'm excited I love to wear stuff like this all the time but it is so low. I try things on, maybe it will work. But then it doesn't and I'm upset. For this high school senior, trips like these end up in tears. Mackenzie is a petite five feet tall. Her bra size, 32-h. Uh-huh, H. So Mackenzie is making a drastic decision to go under the knife to surgically shrink the size of her breasts on her 18th birthday. Someone told me I was going against god. He gave me a gift and I shouldn't be doing this. To them, I want to say, I don't care about your opinion because at the end of the day it's my body. Reporter: It turns out Mackenzie is far from alone. In the U.S., breast reduction surgeries have spiked 157%. Why this uptick? Some studies suggest girls today reach puberty earlier, pointing to the obesity epidemic or hormones in the modern diet. Other experts say it is because the surgery has gotten so safe and artful. Doctors tell us younger and younger women are seeking out the procedure raising questions are teenagers like Mackenzie old enough to understand the risks? Nipple sensitivity, and even losing the ability to breast-feed. I'm ready to take the chance because it will be worth with it in the end. The size of her breasts have taken a physical and emotional toll on her since her early teens. So uncomfortable. The worst part is walking down the street or walking down the hall at school. Being known as the girl with the giant boobs. Having guys date me because I have boobs and it gives me self confidence issues because I feel I can't trust people. Reporter: Two weeks before the surgery. Preop at ten. They are driving two hours to Boston children's hospital for a preop appointment. I asked if I have kids will I be able to breast-feed. What impact will it have on my body. Reporter: She is going to meet one of the best known surgeons. We see patients as young as 12, 13 years of age but that's rare. Dr. Labow specializes in reduction surgeries. A field fraught with controversy. You can have a 15 or 16-year-old more emotionally secure than 18 bra straps that bruise or chafe to the point of bleeding. Physical, social, psychological, self esteem issues are decreased with this. How are you? Great to see you. Reporter: Luckily for Mackenzie her insurance covers the procedure. Otherwise it would cost $10,000, trip Whal the typical breast enlargement would cost. I would think that you would in part be able to breast-feed but we are making it a little more difficult to do so. Reporter: For Mackenzie the long-term benefits out weigh the risks. I want to look like a Normal girl and I have never been so sure of one thing in my life that I want to do. Reporter: The night before surgery we pay Mackenzie a quick trip to her hotel room. How are you feeling? I'm feeling good. Do you know what size you will be when it is over. Maybe a D if I'm lucky, C plus, D. Mom, when you think of the surgery, what comes to mind? I'm nervous, really proud she is definitely going through with something that will impact her for, you know, the rest of her life. It was a very hard decision. Birthday present for you. Hi. Bright and early the morning of her 18th birthday, Mackenzie arrives in preop. Adorable. You can tie it to the stretcher. Officially an adult she signs her first consent form. Mackenzie is allowing us to be with her every moment of her surgery, four hours in total. I'd expect you to recover -- you will be pretty much yourself by the one-week mark. Healing under the dressing is what will play out over time. Most people won't notice anything that has happened but you will feel lighter right away. Reporter: Mom's never waivered in her support of Kenzie, showing no signs of fear until now. Anxious. Hard. This is the moment -- nobody likes -- No. I'm actually really nervous. When they started to mark it, it was like, try to stay strong for her. Reporter: On the table the complicated work begins. Set for incision. Use the scale to weigh how much you removed. For a couple of reasons, documented for the purposes of insurance and also gives me a sense of how much we have done on this side and when we go to the other side we can say we want to be more or less that sort of thing. While the team is sculpting away we went to check in on mom. She is sleeping okay. We went a little after she went to sleep but she's good. Tears coming down my eyes. I know. After nearly four hours the team is done, having removed about a pound from each breast. The surgery went smooth limit it was pretty much what we thought it would be. We didn't take a huge amount of tissue. A proportional amount. She feel lighter. She's going to look really good. Wonder sglfl Mackenzie is groggy and in pain but awake. It's over. Two with weeks later, on the day her bandages come off, Mackenzie is shopping for a senior prom dress for her new figure. Gone is the 32-h. Instead a comfortable 32-d. I love this dress. I didn't feel any different until I got to the different today and they took it off and I looked down and I was like oh, my god. They are gone. So great. I noticed as soon as I woke up on Thursday that my back pain is gone, which is the best thing ever. I can sit up straight without crying because my back used to always hurt. I feel like a completely -- like a new me. Too big on the top. That's a miracle. Reporter: Her dress size has gone from an eight to a zero. She finds the perfect dress. A princess moment without the zipper tug of war. It is almost like I have a new life and stepping in to adulthood as a new person. I like this. I feel like belle.

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