Long-Term Effects of Puberty Blockers: A Sourced Guide for Families

TransHealthHub

Sep 4

6 min read

Key Takeaways

Puberty blockers (also called puberty-pausing medication) pause physical puberty, and for most adolescents, puberty resumes once the medication stops.
You may see this care described as puberty blockers, hormone-suppressing medication, or puberty-pausing medication. This guide uses "puberty-pausing medication" for clarity, and the terms describe the same treatment.
The longer-term area researchers watch most closely is bone density. A 2020 study found bone density measures normalized in transgender boys within a few years of adding hormone therapy, but stayed lower than average in transgender girls at the same point.
Fertility outcomes depend heavily on when in puberty treatment starts and how long it continues, which is why fertility preservation counseling happens before treatment begins.
A large 2026 U.S. study following more than 41,000 transgender youth found this medication was associated with lower odds of a mood disorder or suicidal thoughts diagnosis over time, though the study's authors caution this shows an association, not a proven cause.

The short answer

The best-established long-term effect of puberty-pausing medication is that its core action reverses: puberty generally resumes once treatment stops. What researchers are still working out is how completely some other effects, particularly on bone density, catch up over multiple years, and how much long-term data actually exists for each outcome. At TransHealthHub, we think families deserve to see what multi-year research actually shows across bone density, fertility, growth, and mental health, not just the short-term picture.

This medication has been used for decades to delay early puberty in children generally, and long-term outcomes for transgender adolescents are studied using many of the same tools clinicians have used to track puberty-pausing treatment for other conditions.

What happens once treatment stops

Puberty generally resumes on its own once the medication is stopped, since it pauses puberty rather than reversing anything permanently. Our page on are puberty blockers reversible covers this specific question, including where the evidence on reversal is strongest and where it's still developing, in depth. This page focuses on what happens over the months and years that follow, across each area doctors track.

Bone density over multiple years

Bone density is the long-term effect with the most direct evidence, and it's also the one most often misunderstood. A 2020 study in the Journal of Clinical Endocrinology and Metabolism followed 51 transgender girls and 70 transgender boys in the Netherlands through roughly two years of puberty suppression, then followed a subset, 36 of the girls and 42 of the boys, through three additional years of combined hormone treatment. Bone density scores declined for both groups during the puberty-pausing phase, then increased significantly once hormone therapy began. By the three-year mark, those scores had normalized in transgender boys, but remained below the population average in transgender girls, whose scores had actually started out lower even before treatment began.

The study's authors describe this as an open question for future research, stating plainly that "it is currently unclear whether this results in adverse outcomes, such as increased fracture risk," in transgender girls as they grow older.

A separate, shorter-term 2024 study of 56 transgender youth in the United States found bone density scores were slightly below average across treatment groups, but still within the normal range, including for those on puberty-pausing medication alone. TransHealthHub's page on puberty blockers and bone density walks through both studies and what clinicians do to monitor and support bone health throughout treatment.

Fertility over time

How this medication affects fertility depends heavily on when in puberty a young person starts and how long they continue treatment, and starting earlier in puberty can narrow fertility preservation options later. That's why the Endocrine Society's clinical practice guideline instructs clinicians to counsel every young person on fertility preservation options before puberty suppression begins, not after. Our page on puberty blockers and fertility covers what that counseling looks like and what current research does and doesn't show about long-term reproductive outcomes.

Growth over time

This medication pauses the pubertal growth spurt along with other physical changes, so care teams track height regularly throughout treatment to confirm growth stays on an expected path. The Mayo Clinic's patient guidance notes that height is typically checked every few months during treatment, and that growth generally resumes on its own once the medication is stopped. Long-term studies following final adult height in transgender adolescents who used this medication remain limited, which is one of the genuine open questions in this area.

Mental health over time

Because concerns about this medication are sometimes framed around long-term mental health, it's worth looking at what multi-year evidence actually shows. A 2026 study in JAMA Network Open examined insurance claims for more than 231,000 U.S. youth ages 10 to 17, including over 41,000 transgender youth, and found that a prescription for this medication was associated with lower odds of being diagnosed with a mood disorder and lower odds of suicidal thoughts or behaviors over the claims-observation period, compared with transgender youth who did not receive one. The study's authors were careful to note that claims data show associations, not proof of cause and effect, and that further follow-up research is still needed.

This overall picture is consistent with the position of major U.S. medical groups. The American Medical Association, American Academy of Pediatrics, American Psychological Association, and Endocrine Society continue to regard this care, prescribed and monitored by a qualified clinician, as safe and medically necessary. Our page on are puberty blockers safe covers that consensus, and where the certainty of the long-term evidence is still debated, in more detail.

What's known long-term, and what's still being studied

Long-term area	What multi-year data shows	What's still being studied
Pubertal development	Generally resumes once the medication stops	How closely the resumed timeline matches what would have happened without treatment
Bone density	Normalized in transgender boys by three years into combined treatment in one study; stayed lower than average in transgender girls at the same point	Whether that gap has implications for fracture risk later in life
Fertility	Depends on timing and duration of treatment	Individualized outcomes with longer follow-up
Growth	Growth resumes after the medication is stopped	Final adult height across larger, longer studies
Mental health	Associated with lower odds of mood disorder and suicidal thoughts diagnoses in one large U.S. study	Longer follow-up periods and outcomes reaching into adulthood

Frequently asked questions

What are the long-term effects of puberty blockers? The best-established long-term effect is that puberty generally resumes once the medication stops. Bone density is the effect studied most closely over multiple years, with one study showing scores normalized in transgender boys by three years into combined treatment but remained lower than average in transgender girls at that point.

Does bone density fully recover after stopping puberty-pausing medication? Research shows bone density typically improves once hormone therapy begins, and normalized within a few years in transgender boys in one study, though it stayed below average in transgender girls at the same follow-up point, an open question researchers are still tracking.

Are there long-term mental health effects from puberty blockers? A large 2026 U.S. study found this medication was associated with lower odds of a mood disorder or suicidal thoughts diagnosis among transgender youth over the observation period, though the study's authors note this reflects an association rather than a proven cause, and longer follow-up is still needed.