I would like to know how many kgs do I need to be in order to get my breasts reduced?

Candidates for breast reduction will typically have documented evidence of neck/back and shoulder pain as well as rashes and bra strap grooving attributable to the increased breast weight. They will often demonstrate that these symptoms have been resistant to more conservative measures like therapy, weight loss and pharmacologic intervention. This is needed for insurance coverage.
In addition to establishing a case for medical necessity, there are also requirements for resection weight (when covered by insurance). This may be a standard "500 gm per side" stipulation or a more variable standard based upon body surface area/Schnur scale.
Insurance coverage is contingent on the meeting the requirements (which will vary) for establishing a case for medical necessity.
With regards to your specific question, it is not typically a question of weight but rather body surface area as it relates to breast size.
As always, discuss your concerns with a board certified plastic surgeon (ABPS).
Donovan Rosas MD
Board Certified by the American Board of Plastic Surgery
Member: American Society for Aesthetic Plastic Surgery, American Society of Plastic Surgeons
RealSelf Verified Member
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The weight of breast tissue a plastic surgeon believes he or she can remove during a breast reduction generally varies between 400 and 600 grams. With a BMI over 35, reaching within 10 pounds of your goal weight over a period of several months prior to surgery would lower the risks of complications during and after surgery and enhance results. A Skype or in-office consultation with a board certified PS would be required to verify your candidacy.

Thank you for your question! It is hard to tell without a physical examination of exactly whats going on.  I suggest you seek a board certified plastic surgeon and have a consultation.  Best of luck!Dr Dhaval Patel 
Plastic Surgeon 
Double Board Certified 
Chicago
Hoffman Estates 
Oakbrook 
Orland Park

Thank you for your question. I would recommend that you reach your goal weight before considering breast reduction surgery.

Dear  ZF.nene,
generally speaking, you want to reach your goal weight before you consider a breast reduction, otherwise your results will be suboptimal if you continue to lose weight after the surgery.
Breast reduction is best suited for women who wish to decrease the size of their breasts. While there are different techniques used to perform this surgery, I prefer the vertical incision (lollipop pattern) breast reduction technique instead of the anchor scar pattern, which reduces more noticeable scarring than usual. I also use a SAFE liposuction technique to reduce additional fat around the stubborn axilla area and bra line. This way, my patients are achieving beautiful results with minimal incisions which reduces downtime and delivers an overall better breast shape long term.If you are considering breast reduction surgery, you should consult with a board certified plastic surgeon to discuss your options and make sure your surgeon understands your goals. Only after a thorough examination you will get more information and recommendations.
Daniel Barrett, MD
Certified, American Board of Plastic Surgery
Member, American Society of Plastic Surgery
Member, American Society of Aesthetic Plastic Surgery

Hi and welcome to our forum!
Every
plastic surgeon develops individual criteria for surgery based upon training
and life experience.
BMI
(body mass index equals weight in kg / square of height in meters) is one
criterion to determine the anticipated results of a cosmetic surgery. You
can find BMI calculators on the internet. If your BMI is > 30, the cosmetic
result will not be optimal. If your BMI is > 35, your operative risk will
rise. YOUR BMI is 35.16,  In our practice we recommend a BMI of < 30, which corresponds to a weight of 75 kg. 
We
recommend that you be at a healthy comfortable stable body weight at the time
of surgery. The cosmetic effect improves with lower BMIs. 
We
recommend a regimen of diet and exercise to reach a safe and healthy body
weight. If not achievable, one may consider a bariatric procedure such as a
gastric sleeve to achieve dramatic weight loss.
Visit
a board certified plastic surgeon for in-person evaluation and discussion.
Best wishes...