Amr Alfiky/Reuters
Gender-affirming surgery can help shape the body of a transgender or nonbinary person to more closely align with the gender with which they identify.
CNN  — 

The number of gender-affirming surgeries done in the United States nearly tripled between 2016 and 2019, a new study shows.

The increase is probably due in part to changes in state and federal laws that require insurance to cover such care, in addition to some growing social acceptance of the trans community, according to the authors of the paper, published Wednesday in the journal JAMA Network Open.

Earlier studies have detected an increasing trend in earlier time periods, but they typically captured only inpatient procedures. Many gender-affirming surgeries are outpatient, study co-author Dr. Jason Wright said.

“There has been a general feeling that there are more patients who are seeking these procedures and looking for expertise, and there really wasn’t a lot of great data to quantify the numbers,” said Wright, who is the Sol Goldman Associate Professor of Obstetrics and Gynecology and chief of the Division of Gynecologic Oncology in the Columbia University College of Physicians and Surgeons.

Gender-affirming surgery, also called gender confirmation or sex reassignment surgery, is a procedure or series of procedures that can help shape the body of a transgender or nonbinary person to more closely align with the gender with which they identify.

Not every person who identifies as transgender or nonbinary will choose surgery. It’s usually done as one of the later steps in gender-affirming care, the medically necessary, evidence-based care that uses a multidisciplinary approach to help a person transition from their assigned gender – the one the person was designated at birth – to their affirmed gender – the gender by which one wants to be known.

For the new study, the researchers looked at records from 2016 to 2020 from the Nationwide Ambulatory Surgery Sample, the largest all-payer surgery database in the US that tracks people who have had procedures that don’t require an overnight hospital stay, and the National Inpatient Sample, the largest publicly available all-payer database of people who have had to stay in the hospital when they have surgery.

The researchers looked for patients whose records had a diagnosis code for “gender identity disorder,” a personal history of sex reassignment, or the word “transsexualism.” Though now considered outdated or offensive, that term is sometimes used in medical records.

The study found that more than 48,000 people had at least one gender-affirming surgery during this time period. They included breast or chest procedures, often called “top surgery,” which made up more than 56% of the surgeries. People who had genital reconstructive procedures, often called “bottom surgeries,” made up more than 35% of the procedures. Facial and other cosmetic procedures were also included in this research.

The number of gender-affirming surgeries rose from 4,552 in 2016 to 13,011 in 2019, declining only slightly to 12,818 during the first year of the Covid-19 pandemic, when many hospitals cut back on all surgeries. The number of medical appointments related to gender identity disorder rose from 13,855 in 2016 to 38,740 in 2020, the study found.

The majority of the patients were 19 to 30 years old, making up more than 52% of the surgeries. Breast and chest procedures were twice as common as genital procedures among that age group.

More than 21% of the people who had surgery were 31 to 40. Genital surgeries were more common among those older than 40.

The study found that a fraction of gender-affirming surgeries – about 7% – were done on patients ages 12 to 18, but some experts think that number sounds high. Wright said the majority of these surgeries tended to be among 17- and 18-year-olds and were the less-invasive procedures like breast or chest procedures.

Surgery is not typically recommended until adulthood, and in some states, surgeries on teens are illegal.

Dr. Devin Coon, a board-certified plastic surgeon in the Division of Plastic Surgery at Brigham and Women’s Hospital and an associate professor of surgery at Harvard, was not involved with the new research but says it captures trends he sees in the operating room.

He says, however, that because there’s no one procedure code for gender-affirming surgery like there is with more common surgeries like knee replacements, the numbers in the new study can’t be as specific. He thinks they’re probably undercounted instead.

“It’s very easy to say who had a knee replacement. It is not like that for gender-affirming surgeries,” Coon said. “It is reasonable to look at the study, though, and say the trends in here are probably reflective of the overall trends.”

Study co-author Wright said the data sources they used were the best of what is available, but he acknowledges their limitations. For instance, these databases don’t capture surgeries done in every state.

“I would say that the true number of surgeries are probably even a little bit higher than this,” he said.

Research has supported the positive effects of gender-affirming care.

For trans and nonbinary adults, recent studies show, surgeries are highly successful and offer significant physical and mental health benefits, including better mental health, a reduction in suicidal thoughts, a better quality of life and a higher rate of general life satisfaction. Surgeries even have indirect health benefits, studies show, such as reducing the number of people who smoke.

Major medical associations – including the American Medical Association, the American Psychiatric Association, the American Academy of Pediatrics and the American Academy of Child & Adolescent Psychiatry – agree that gender-affirming care that can include surgery for adults is clinically appropriate and sometimes even life-saving.

Studies also show consistently that people who have surgeries to help their body match their gender are extremely satisfied and generally do not change their minds later, as some critics have suggested.

One review of studies published in 2021 found that of those who underwent transfeminine and transmasculine procedures, only 1% regretted it.

Wright and Coon say the new research demonstrates that there is an increased need for surgeons specifically trained to work with trans and nonbinary patients. Demand for gender-affirming surgeries continues to rise. One study found that the number of inpatient procedures nearly doubled between 2000 to 2005 and from 2006 to 2011, yet the number of specifically trained surgeons has not kept pace.

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“No procedure is obviously uncomplicated, but I think particularly with some of the facial procedures and some of the genital reconstructive procedures, can be quite specific and fairly significant operations for patients to undergo. So I think making sure that expertise is available to patients, I think it’s definitely a take-home from this study from a policy standpoint,” Wright said.

Coon started a fellowship at Harvard to provide specific gender-affirming surgical training.

“A lot of these surgeries are just so complicated, so it’s important to produce a group of people who are skilled at doing this,” he said. “We see a lot of patients who got not great surgery because the person doing it wasn’t super well-trained, so we would certainly like a dedicated workforce and supervised education to expand patients’ options.”