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International Journal of Transgender Health logoLink to International Journal of Transgender Health
. 2025 Jan 21;27(1):542–552. doi: 10.1080/26895269.2025.2452996

The evolution of pediatric transgender healthcare in Flanders: Trends in referrals, intakes and gender-affirming interventions over the last 15 years

Silvia Ciancia a, Laura Bruneel b, Judith Van Schuylenbergh b, Daniel Klink c, Karlien Dhondt d, Robin Heyse e, Joz Motmans b, Martine Cools a,c,✉
PMCID: PMC12857706  PMID: 41625013

Abstract

Purpose

The expanding number of minors questioning their gender identity and seeking care has led to the constitution of pediatric gender clinics in several countries. The activity of the multidisciplinary Pediatric Gender Team at Ghent University Hospital, Belgium started in 2007. We report on the evolution of referrals, psychological intakes, and trends in the start of gender-affirming medical and surgical interventions from 2007 to 2023.

Methods

The whole cohort of minors (age <17 years) having a psychological intake between 2007 and 2023 was included. Subgroups were analyzed based on sex registered at birth (female or male, RFAB and RMAB respectively), year and age at the psychological intake (below or above 10 years).

Results

Referrals have increased in recent years. Between 2007 and 2023, 890 minors (65.5% RFAB) accessed our service. The ratio RFAB/RMAB has progressively increased, and RFAB with age at first intake >10 represented the greatest proportion. After 12 months, 19.5% were no longer in follow-up at our center; 28.1% of RFAB and 47.2% of RMAB did not start any medical treatment; 66.9% of RFAB and 52.8% of RMAB started gonadal hormone suppression (GHS), achieved with gonadotropin-releasing hormone analogues in 17.7% of RFAB and 34.6% of RMAB, with pro-androgenic progestins in 82.3% of RFAB and with anti-androgens in 65.4% of RMAB. 74.6% of RFAB and 86.4% of RMAB on GHS and older than 16 started gender-affirming hormones. Mastectomy was the most common gender-affirming surgery in RFAB, followed by hystero-gonadectomy. Gender-affirming surgery in RMAB was less frequent; vaginoplasty was the most frequent procedure.

Conclusions

The care of minors with gender incongruence requires a multidisciplinary approach due to the complex psychological, social, and physical needs of this group. The timing and therapeutical options must be tailored to each adolescent.

Keywords: adolescents; children; gender incongruence; gonadotropin-releasing hormone analogues; progestins, gender-affirming hormones; transgender

Introduction

In the last years the number of transgender and gender diverse (TGD) people seeking psychological support and/or medical care has increased. Accordingly, gender identity services have witnessed a steep increase in the number of referrals and work load (Arnoldussen et al., 2020; Kaltiala et al., 2020; Service, n.d.; Wiepjes et al., 2018). In parallel, the age at which TGD people present at gender clinics has decreased (Wiepjes et al., 2018), leading to the constitution of dedicated pediatric gender clinics.

In the last years, several studies have been consistent in showing improved or stable psychological functioning, body image, and treatment satisfaction, although differences in treatment protocols and methods hinder uniform conclusions (Achille et al., 2020; Becker-Hebly et al., 2021; Carmichael et al., 2021; Kuper et al., 2020; Tordoff et al., 2022).

In 2007, the Pediatric Gender Team (PGT) of Ghent University Hospital started its activity and has for long been the only pediatric gender service in Belgium. A multidisciplinary team involving child psychologists, child psychiatrists, social workers, and pediatric endocrinologists was created. In addition, plastic surgeons, urologists and gynecologists with experience in counseling and treatment of TGD persons collaborated since the beginning. From the start, we offered various alternatives to gonadotropin-releasing hormone analogues (GnRHa), which have been used as first choice medication for gonadal hormone suppression (GHS) since the start of medical care for TGD adolescents (de Vries & Cohen-Kettenis, 2012). Initially, this was because of limitations in the reimbursement criteria for GnRHa. With reimbursement secured for all persons from 2022 onward, alternatives to GnRHa have been prescribed to achieve GHS as a first choice in specific situations, offering individualized care.

The first aim of this study was to investigate evolutions in the number of children and adolescents referred to our PGT and receiving a psychological intake since 2007. Secondly, we wished to analyze how many decided to proceed with GHS after being diagnosed with gender incongruence/gender dysphoria (GI/GD), and how many subsequently continued with gender-affirming hormones (GAH). Differences between the alternative protocols for GHS were also explored. Furthermore, we looked at how many individuals were still taking GAH at the moment of the data acquisition, and how many decided to proceed with gender-affirming surgery (GAS). Lastly, we analyzed how many minors eventually stopped the treatment in our center.

Methods

Study population and design

Data acquisition took place between December 2023 and February 2024, checking each medical file to update and implement our institutional database, which is regularly updated by the case managers of the PGT. All children and adolescents who underwent at least one consultation with a pediatric psychologist within the PGT between 2007 and 2023 were included. Only minors younger than 17 were eligible for the psychological intake. Of note, minors do not need to be referred by their general practitioner or a specialist; they (or their parents) can auto-refer themselves asking for an appointment with a pediatric psychologist. The following data were collected: date of birth, sex registered at birth (SRAB, with only two legal options available in our country), experienced gender, age at referral, age at first intake with a pediatric psychologist, age and Tanner stage (and prescribed medications) at start of GHS and GAH, age at GAS (if any), continuation or discontinuation of GHS or GAH at the moment of data acquisition. If GHS and/or GAH were discontinued, the reasons behind this decision were searched. The evolution of numbers and age of minors on the waiting list were also acquired, regardless of whether the first intake occurred.

Treatment protocol

Since the start of the PGT activity until September 2022, the treatment protocol has remained largely unchanged and is in line with current guidelines (Coleman et al., 2022; Hembree et al., 2017). However, from 2018 onward, only children above the age of nine have been considered eligible for a psychological intake within our PGT, while younger children are referred to an external child psychologist. Specifically, minors reporting GI feelings are assessed by a pediatric psychologist for at least 6–12 months, with appointments every 4–6 weeks. During these sessions, gender identity is explored, next to romantic relationships and sexuality. The overall mental health, contextual factors, such as family support, socioeconomic and educational context are carefully considered, and when necessary the minor is referred for external support or specific psychotherapy. Psychological follow-up is continued throughout the transition pathway. Each medical step is discussed within the multidisciplinary team. An evaluation by a child psychiatrist and involvement of a social worker is mandatory before the start of GnRHa, GAH or any surgical intervention. The advantages and disadvantages of any medical or surgical step are discussed thoroughly by all health care professionals involved. Minors are referred to the pediatric endocrinologist to stage pubertal development (Marshall, 1975) or to start with GHS or GAH. Several options exist for GHS, optimizing individual care, and the use of specific medications has changed over the years, see Figure 1. The start of GAH has been reserved for a long time to minors older than 16 years, however according to the latest guidelines (SOC8) the age of 16 does no longer represent a restriction to start GAH (Coleman et al., 2022). Other aspects, such as mental maturity, prolonged GHS and psychological wellbeing, are taken into account to determine the optimal timing. In RFAB, testosterone is usually started at a dose of 50 mg i.m. every 2 weeks and progressively increased every 6 months to an adult replacement dose (on average 125 mg/2 weeks i.m.). In older adolescents (>17 years old) the starting dose can be higher. In RMAB, estradiol valerate is usually started at a dose of 0.5 mg/day orally and increased to 1 mg/day after 6 months and to an adult ­replacement dose of 2–4 mg/day after 24 months. Transdermal estrogens (e.g. patches or gel) are rarely prescribed for reimbursement reasons or adolescent’s preference. Gender-affirming surgeries are performed only in adults (>18 years) with the exception of mastectomy which can be offered by the age of 17.

Figure 1.

Figure 1.

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Protocol for GHS and its variation over the time. From September 2022 GnRHa became reimbursed also for late-pubertal adolescents.

Statistical analysis

The whole cohort of minors who had an intake between 2007 and 2023 was divided in two groups based on SRAB. Subsequently, smaller cohorts were made to analyze trends over time, based on year at intake (with 3-year intervals except for the last 2 years 2022–2023). We then compared the trends over time and the proportion of children starting with GHS and/or GAH, taking into account the age at first intake (below or above 10 years, as a proxy measure for starting the psychological trajectory before or after onset of puberty).

The analysis was performed with Microsoft 365 Excel (version 2403) and the graphical representation was performed with GraphPad Prism version 10.

Normally distributed data are reported as mean ± SD, while non-normally distributed data are reported as median (IQR). Dichotomous variables are reported as percentages.

Results

Trends over the years

Between 2007 and 2023, 890 minors (65.5%, n = 583 RFAB and 34.5%, n = 307 RMAB) had at least one consultation with a pediatric psychologist within the PGT. The median age at the intake was 15.05 (IQR 3.64) for RFAB and 13.93 (IQR 6.15) for RMAB. An increase in the number of minors referred to our team has been observed since 2017, reaching a plateau in 2021. The number of referrals has exceeded the number of intakes since 2017 in spite of staff expansion, resulting in a progressively increasing waiting list. The increase in the number of referrals per year and the number of minors having a psychological intake stratified per year are shown in Figure 2(a), with RFAB minors representing the majority of those who had psychological intake, as shown in Figure 2(b). Figure 3 shows the evolution of median age at psychological intake, at start of GHS and at start of GAH for RFAB and RMAB. Over the years, a reduction of the time between psychological intake and start of medical transition was observed. Trends are shown in Figure 4, based on the SRAB. In Figure 5, the percentage of individuals starting GHS and GAH are shown, divided per SRAB and stratified per year at the first intake. Of note, for the last three intervals, data are influenced by the time of data acquisition, with a part of the population not being eligible yet to start GHS and/or GAH. Moreover, in our center progestins and CPA have been the preferred drug for GHS in late-pubertal RFAB and RMAB respectively until 2022, as GnRHa were not reimbursed for minors in Tanner stages 4 and 5. However, the approval of GnRHa reimbursement in Belgium for all TGD individuals in September 2022 has led to an increase in the use of GnRHa only in RMAB but not in RFAB minors.

Figure 2.

Figure 2.

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(a) Number of referrals and intakes with a pediatric psychologist within the PGT at Ghent University Hospital between 2007 and 2023. The two peaks in intakes (2017–2018 and 2021–2022) were due to more psychologists joining the team, increasing the intake capacity. RFAB and RMAB are shown together. (b) Ratio based on SRAB for minors who had the psychological intake, stratified per year of intake, from 2007 to 2023. The year 2007 is not shown because only one RMAB minor receive the psychological intake.

Figure 3.

Figure 3.

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Median age (IQR) at the psychological intake, start of GHS and start of GAH for adolescents RFAB and RMAB.

Figure 4.

Figure 4.

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Time between intake with the pediatric psychologist and start of GnRHa, progestins (P) for adolescents RFAB or CPA for adolescents RMAB, and GAH. Time is expressed in months (median and IQR); data are stratified per year at the intake.

Figure 5.

Figure 5.

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Proportion of adolescents starting GnRHa, progestins (P) for adolescents RFAB or CPA for adolescents RMAB, and GAH divided per SRAB and stratified per year at psychological intake. For the last three intervals, data are influenced by the time of our data acquisition.

Additionally, we registered how many minors decided to stop psychological follow-up after 1 year from the first intake. The analyzed interval was 2017–2022, as this information was not systematically registered before 2017, while the end of data collection in February 2024 did not allow us to acquire this information for intakes happening in 2023. According to the data for 2017-2022, the proportion of children/adolescents who stopped with the follow-up 1 year after the psychological intake, were 18% for intakes in 2017, 24% for intakes in 2018, 14% for intakes in 2019, 25% for intakes in 2020, 17% for intakes in 2021, and 19% for intakes in 2022; on average 19.5% per year.

Overview of medical interventions

Of all minors receiving a psychological intake, 28.1% and 47.2% of RFAB and RMAB respectively did not start any medical treatment at the moment of data acquisition. The median time between psychological intake and the start of GnRHa was 15.2 months (IQR 18.3) for RFAB and 21.1 months (IQR 40.1) for RMAB; progestins were started 9 months (IQR 9.8) after the psychological intake, CPA 11.4 months (IQR 11.4). The median duration of psychological follow-up from the intake to the start of GAH was 20.7 months (IQR 21.4) for RFAB and 24.8 months (IQR 28.6) for RMAB.

Among all RFAB minors, 66.9% started GHS, of whom 17.7% with GnRHa and 82.3% with progestins. Of the 307 RMAB, 52.8% started GHS, of whom 34.6% started with GnRHa and 65.4% with cyproterone acetate (CPA). Age and Tanner stage at the start of GHS are shown in Table 1.

Table 1.

GHS and GAH in TGD minors evaluated within the PGT at Ghent University Hospital between 2007 and 2023.

  RFAB RMAB
Total sample (n = 890) 583 (65.5%) 307 (34.5%)
Starting GHS 390 (66.9%) 162 (52.8%)
Type GHS GnRHa
(n = 69, 17.7%)		 Progestins
(n = 321, 82.3%)		 GnRHa
(n = 56, 34.6%)		 CPA
(n = 106, 65.4%)
Age at start 11.95 (2.04) 16.41 (1.89) 13.99 (3.39) 16.67 (1.86)
Tanner 2 23 (33.3%) 0 (0%) 18 (32.1%) 0 (0%)
Tanner 3 23 (33.3%) 4 (1.2%) 18 (32.1%) 5 (4.7%)
Tanner 4 9 (13.1%) 47 (14.7%) 1 (1.8%) 20 (18.9%)
Tanner 5 5 (7.2%) 215 (67%) 10 (17.9%) 61 (57.5%)
Tanner NA 9 (13.1%) 55 (17.1%) 9 (16.1%) 20 (18.9%)
Duration GHS (years) 3.01 (1.53) 0.82 (0.83) 2.12 (2.12) 0.82 (0.65)
Starting GAHa 35 (94.6%) 256 (85.3%) 42 (84%) 98 (94.2%)
Age at start GAH 17.10 (1.79) 17.13 (2.03)
Still on GAH Yes No NA Yes No NA
  293 (91.6%) 10 (3.1%) 17 (5.3%) 127 (90.7%) 0 (0%) 13 (9.3%)
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Age and years are expressed as median (IQR). GHS: gonadal hormone suppression. GAH: gender-affirming hormones. NA: not available.

aPercentage is calculated on the total number of adolescents on GHS and aged 16 or older. Of note, 29 RFAB did not use GHS before the start of GAH or assumed OAC.

With regard to GAH, 94.6% of RFAB on GnRHa and 85.3% on progestins and aged 16 or older started testosterone supplementation. Of the total 320 RFAB starting GAH, 9% did not use GHS before the start of GAH or assumed oral anticonception pill (OAC). Among RMAB aged 16 or older and on GnRHa or CPA, 84% and 94.2% respectively started estrogen supplementation. The duration of GHS before starting GAH, the age at start of GAH and the percentage of individuals continuing with GAH are shown in Table 1.

Table 2 offers an overview of the proportion of individuals undergoing GAS and the median age at time of the procedure.

Table 2.

Access to gender-affirming surgery.

Masculinizing surgery RFAB Feminizing surgery RMAB
Mastectomy a 263 (97.8%) Breast prosthesis 43 (35.5%)
Age at mastectomy 17.98 (1.35) Age at breast prosthesis 19.03 (1.78)
Hysterectomy b 147 (54.6%) Orchidectomy c 8 (6.6%)
Age at hysterectomy 19.0 (1.65) Age at orchidectomy 19.64 (3.30)
Metoidioplasty 20 (7.4%) Vaginoplasty 72 (59.5%)
Age at metoidioplasty 20.43 (1.94) Age at vaginoplasty 19.03 (1.64)
Phalloplasty 52 (19.3%) FFS 4 (3.3%)
Age at phalloplasty 20.31 (2.36) Age at FFS 20.59 (5.16)
Penile implant 16 (5.9%) Chondrolaryngoplasty 3 (2.5%)
Age at penile implant 21.97 (1.90) Age at Adam’s apple surgery 19.86 (3.27)
Testicular prosthesis 22 (8.2%) Voice feminization surgery 10 (8.3%)
Age at testicular prosthesis 21.9 (1.73) Age at voice feminization surgery 19.51 (2.77)
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Age is expressed as median (IQR). Percentages are calculated on the total of individuals who started GAH and aged 18 or older. FFS: facial feminization surgery.

aEleven additional RFAB underwent mastectomy without assuming GAH.

bOne person removed only one ovary; another person left both ovaries in situ. All the others underwent hystero-ovariectomy.

cWithout vaginoplasty.

A limited number of individuals decided to stop (partially or completely) the gender transition trajectory and, unfortunately, five RFAB individuals died by suicide, see Figure 6.

Figure 6.

Figure 6.

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Discontinuation of gender transition trajectories.

The median age at which suicided was committed was 18.6 years (range 17.9–20). Four of these individuals had started medical transition during late puberty with GHS followed by GAH; they had also undergone mastectomy and hysteron-gonadectomy at the time of suicide. One individual had started medical transition with GAH without previous GHS, and had undergone hysteron-gonadectomy. No increase over time was registered (one event in 2014, one event in 2015, two events in 2018 and the last one in 2019).

Access to medical care depending on the age at intake

Lastly, we calculated the percentage of minors starting GHS and/or GAH depending on the age at first intake (below or above 10). The considered interval for these data is 2007–2017 because, according to our internal policy, from 2018 onward only children aged >9 are eligible for intake. Moreover, young children having an intake in more recent years would still not be eligible for medical steps. Figure 7 shows the proportion of minors undergoing psychological intake stratified for year and age at the intake, and for the SRAB. With regard to the proportion of minors starting GHS and/or GAH stratified for year and age at the intake, and for the SRAB, the percentages vary over the years. However, minors receiving psychological intake after the age of 10 were more likely to start GHS (76–96% for RFAB and 68–97% for RMAB) or GAH (67–97% for RFAB and 50–77% for RMAB) as compared to those having psychological intake at an age younger than 10 (GHS started in 40–67% of RFAB and 25–50% of RMAB; GAH started in 68–70% of RFAB and 44–50% of RMAB).

Figure 7.

Figure 7.

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Proportion of minors who had the psychological intake stratified per SRAB and age at the intake. Data after 2017 are not shown because of internal policy change. The year 2007 is not shown because only one RMAB minor received the psychological intake (age at intake <10). For further explanation see text.

Discussion

In this study, we reported on trends in referrals, psychological intakes and gender-affirming trajectories of TGD minors accessing the Pediatric Gender Service at Ghent University Hospital between 2007 and 2023. Whereas during the first years of activity referrals were variable, from 2017 a progressively greater number of minors were referred to our service for psychological evaluation. Despite the increasing number of pediatric psychologists joining the team, the time on the waiting list increased substantially. This upward trend in referrals and subsequently long waiting lists, is in line with observations in other countries (Arnoldussen et al., 2020; Kaltiala et al., 2020; Service, n.d.; Wiepjes et al., 2018). In line with previous reports, initially we observed an increase in the ratio RFAB/RMAB in the intakes, which seems to be more stable in most recent years. However, this increase was only seen in RFAB adolescents, while numbers of RFAB children have remained unchanged (Cass, 2024; Chiniara et al., 2018; de Graaf et al., 2018; van der Loos et al., 2023). Explanations based on sociological and sociocultural factors have been hypothesized, mainly linked to the greater acceptance of transmasculine behaviors/identities and social media influence, which appears to be stronger among RFAB adolescents (Cass, 2024; Rawee et al., 2024), impacting referral patterns.

With regard to the age at the first psychological intake, as a results of small numbers in the beginning years and the above mentioned change in policy from 2018 onward, most minors were older than 10, and the proportion of minors proceeding with GHS and GAH was higher for those with older age at the intake, in line with the data shown by colleagues (van der Loos et al., 2023).

Above all in childhood, gender variance is not uncommon (Simons et al., 2014). Recent data has showed that among children who started social transition during childhood (median age 8 years), only 7% had re-transitioned 5 years later (Olson et al., 2022).

Based on our experience since 2007, we offer gender questioning minors a thorough psychological assessment before starting any form of transition, and in a setting where multidisciplinary care is offered. Social transition is the first step taken, allowing the minors to further explore their gender identity. Medical transition will follow, if desired, when appropriate age and mental capacity are reached, after multidisciplinary discussion. However, this should not delay treatment for those minors in whom GI/GD is confirmed and delaying treatment could be harmful.

To manage the increase in referrals, since 2018 only children aged >9 have been considered eligible for psychological intake within the PGT. Probably due to this change in internal policy and the longer time on the waiting list, the median age at the first intake with the pediatric psychologist has increased over the years, especially for children RMAB, and a similar trend was seen in the median age at start of GHS and GAH. Conversely, the time between psychological intake and start of GHS and GAH has been progressively reducing.

Among RFAB minors starting GHS, more than 80% were started on progestins while less than 20% received GnRHa (of whom 67% were in the earlier phase of puberty, Tanner stages 2 and 3). With regard to RMAB minors, up to a third underwent GHS with GnRHa (of whom 64.2% starting at Tanner stages 2 and 3). GnRHa is often preferred to CPA in RMAB minors, due to side effects of the latter and because an association between CPA and meningioma has been described, although only for long-term use of high doses of CPA (Champeaux-Depond et al., 2021; Glintborg et al., 2021; Mancini et al., 2018; Tack et al., 2017). Differently, for end-pubertal RFAB minors the main therapeutic goal (i.e. suppression of menstrual bleeding) can be safely achieved through progestins administration. Moreover, a better outcome on bone mineral density has been described (Tack et al., 2018), the oral administration does not require home nursing or regular appointments with the general practitioner, and in our experience, TGD adolescents themselves often prefer them over GnRHa. Importantly, according to our protocol, a consultation with the pediatric psychiatrist is not required before the start of oral progestins and as for the OAC pill, they can be prescribed by general practitioners while waiting for psychological intake to occur. Also, in minors for whom the diagnosis of GI/GD can be confounded by other co-factors, oral progestins are often preferred by our team to achieve GHS as compared to GnRHa.

The start of GHS at a very young age has often been criticized (Brierley et al., 2024; Vrouenraets et al., 2021, 2023). However, in our cohort, and in line with other reports (van der Loos et al., 2022, 2023), the vast majority of minors started with GHS at a median age of 16.41 (IQR 1.89) and 16.67 (IQR 1.86) for RFAB and RMAB, respectively. Median age at the start of GAH was 17 years for both groups. According to our data, 91.6% of RFAB individuals and 90.7% of RMAB individuals were still on GAH at the moment of the data acquisition. Of 5.3% RFAB and of 9.3% RMAB no information was available on this matter, and it was impossible to retrieve if GAH were still prescribed by another center or by a general practitioner. According to our reports, none of the individuals RMAB stopped GAH, while 1.6% of RFAB did, for various reasons (evolution toward non-binary identity, desire of only partial virilization, mental impact after first injection).

With regard to GAS, almost all eligible RFAB underwent mastectomy, while around half underwent a hystero-ovariectomy. Among RMAB, 66% underwent vaginoplasty and/or orchidectomy. New legislation for transgender persons in Belgium was introduced in 2018, according to which transgender persons are no longer required to undergo gonadectomy in order to legally change their gender. It is currently too early to investigate the impact of this legislation in the cohort of minors.

Lastly, it is relevant to highlight that not all minors referred to a gender service for psychological evaluation wish to undertake some form of medical transition. In some cases the gender variant behavior is not indicative of GI and will not persist; in others the gender variant identity does not cause such a psychological burden leading to medical decisions; a change in gender role, modification of gender expression or other coping mechanisms might be alternatives to medical transition. In our total cohort, 28.1% RFAB and 47.2% RMAB did not start any medical treatment, but these percentages could represent an overestimation due to the fact that some minors who are still in psychological follow-up did not meet the criteria yet to start medical transition (age, onset of puberty, stability of the psychological assessments) at the moment of data acquisition. Also, according to the data for 2017–2022, the proportion of minors who stopped with the follow-up 1 year after the psychological intake, was on average 19.5% per year. Reasons for stopping treatment in our center are not always mentioned consistently in the electronic patient files, and can be manyfold (lack of GI, distance to the center, financial reasons, etc.). Previous research in our center reported that some adolescents may resume the trajectory later (Van Cauwenberg et al., 2020).

In conclusion, our data confirm the increase of TGD young people seeking psychological and medical care, in line with the trends observed in other European gender clinics (Kaltiala et al., 2020; Service, n.d.; Wiepjes et al., 2018). Late-pubertal RFAB adolescents represented the most substantial subgroup. By expanding options for GHS beyond GnRHa, we have been able to offer individualized care in specific groups of minors. The recent launch of a European Registry for transgender minors who receive medical care (available at https://eurreb.eu/registries/core-registry/condition-specific-modules/gender-incongruence/) will enhance collaboration among centers and can become a desirable strategy to better investigate these and other trends. Together with other multicentric international collaboration projects (e.g. ENIGI (European Network for the Investigation of Gender Incongruence) study for TGD minors) (Boogers et al., 2024), it lays the foundation for long-term follow-up and scientific data acquisition in transgender minors, and will be highly instrumental to address the current criticism around the use of GnRHa in TGD minors.

Glossary

Abbreviations

CPA

cyproterone acetate

GAH

gender-affirming hormones

GAS

gender-affirming surgery

GD

gender dysphoria

GHS

gonadal hormone suppression

GI

gender incongruence

GnRHa

gonadotropin-releasing hormone analogues

OAC

oral anticonception pill

PGT

Pediatric Gender Team

RFAB

registered female at birth

RMAB

registered male at birth

SOC8

Standards of Care version 8

SRAB

sex registered at birth

TGD

transgender and gender diverse

Funding Statement

This work is supported by a project grant from the Research Foundation—Flanders (FWO; G065819N). MC is supported by a FWO senior clinical investigator grant (FWO; 1801018N) and by a Ghent University Fund for Innovation and Clinical Research (FIKO IV) grant.

Author contributions

Study conceptualization: SC, DK, MC. Funding acquisition: MC. Data acquisition: SC, LB, JVS. Writing of the first draft: SC. Revision of the manuscript: LB, JVS, DK, KD, RH, JM, MC. All authors approved the final version of the manuscript.

Ethical approval and patient consent

All data have been collected retrospectively and analyzed anonymously. Our institutional database is regularly updated by the case managers of the Pediatric Gender Team. None of the subject underwent any study procedure. All standard procedures were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.

Disclosure statement

The authors have nothing to disclose.

Data availability statement

All data generated or analyzed during this study are included in this published article or are available from the corresponding author upon reasonable request.

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Associated Data

This section collects any data citations, data availability statements, or supplementary materials included in this article.

Data Availability Statement

All data generated or analyzed during this study are included in this published article or are available from the corresponding author upon reasonable request.

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