From the Guidelines
A potential side effect of a gonadotropin-releasing hormone (GnRH) analog in a 12-year-old trans boy is reduced height velocity and potentially reduced peak bone mass accrual. GnRH analogs are used to suppress puberty, allowing the child and their family to consider their gender identity and make a decision about masculinizing or feminizing gender-affirming hormone therapy 1. The suppression of sex hormones can impact bone development during this critical growth period. According to the study published in Anaesthesia in 2024, GnRH analogs have been shown to reduce suicidality and improve psychological function, but they can also have adverse effects on bone health 1.
Some key points to consider:
- GnRH analogs are reversible and allow for a temporary halt in the development of irreversible secondary sexual characteristics 1
- Regular monitoring of bone density through DEXA scans is recommended for patients on GnRH analogs 1
- Adequate calcium intake and vitamin D supplementation can help mitigate the risk of reduced bone mass accrual 1
- Weight-bearing exercise is also important for maintaining bone health while on GnRH analogs 1
It's worth noting that the study published in Annual Review of Medicine in 2023 discusses the effects of hormone treatment on trans men, but it does not provide specific information on the side effects of GnRH analogs in 12-year-old trans boys 1. However, the study published in Anaesthesia in 2024 provides more relevant information on the use of GnRH analogs in trans adolescents 1. The most recent and highest quality study, published in 2024, suggests that reduced height velocity and potentially reduced peak bone mass accrual are potential side effects of GnRH analogs in trans adolescents 1.
From the FDA Drug Label
5.3 Metabolic Syndrome The use of GnRH agonists (including TRELSTAR) may lead to metabolic changes such as hyperglycemia, diabetes mellitus, and hyperlipidemia. 5.8 Laboratory Test Interactions Chronic or continuous administration of TRELSTAR in therapeutic doses results in suppression of pituitary-gonadal axis.
A potential side effect of a gonadotropin-releasing hormone (GnRH) analog, such as triptorelin, in a 12-year-old trans boy is metabolic changes, including:
- Hyperglycemia
- Diabetes mellitus
- Hyperlipidemia It is essential to monitor for changes in serum lipids, blood glucose, and/or glycosylated hemoglobin (HbA1c) periodically in patients receiving TRELSTAR and manage according to institutional guidelines 2.
From the Research
Potential Side Effects of GnRH Analogues
A potential side effect of a gonadotropin-releasing hormone (GnRH) analog in a 12-year-old trans boy is a decrease in bone mineral density (BMD) or bone mineral apparent density (BMAD) [ 3, 4,5 ].
- Decreased bone turnover markers (BTMs) such as P1NP and ICTP have been observed during GnRHa treatment 5.
- A decrease in BMAD Z-scores, particularly in the lumbar spine, has been reported in transboys during GnRHa treatment 3, 4, 5.
- However, it is essential to note that the addition of cross-sex hormone therapy (CSHT) may lead to an increase in BMAD and a return of Z-scores towards normal 5.
Long-term Effects
The long-term effects of GnRH analogues on bone health in transgender adolescents are not yet fully understood 3, 4, 6.