Women with Turner syndrome face a raised risk of reduced bone mineral density, a direct consequence of the primary ovarian insufficiency that comes with the karyotype. Oestrogen replacement is the cornerstone of care, but for years a practical question has lingered: does the route of administration matter? Is a daily tablet better than a skin patch when it comes to protecting bone over the long term?
An Austrian team has tackled that question in a pilot study published in Gynecological Endocrinology. They gathered 40 patients with Turner syndrome treated with either oral or transdermal oestradiol, with a median age of 22 years in both groups and a median body mass index of 23.1 in the transdermal group versus 25.4 in the oral one. All of them underwent DEXA scans of the lumbar spine and femoral neck at baseline and again at follow-up. The primary outcome was the t-score at both sites, and the researchers also looked for factors linked to a falling t-score.
The starting point was already telling: at baseline, 38.3% of the participants had osteopenia and 3.3% had osteoporosis — nearly four in ten already had weaker bones despite being on treatment. Over follow-up, 47.5% of patients saw their t-score drop at at least one of the measured sites. Yet when the two routes of administration were compared, no significant differences emerged in absolute t-scores, in how much those scores changed, or in the share of patients whose bone health declined (all p values above 0.05).
The most useful finding came from the multivariable analysis: lower vitamin D levels at follow-up were independently associated with a declining t-score. In other words, among all the variables studied, vitamin D status stood out as the most relevant modifiable factor behind bone loss.
The authors conclude that, in patients with Turner syndrome, the route of oestradiol administration does not appear to significantly affect long-term bone mineral density. At the same time, they warn that a substantial proportion of patients continue to lose bone despite hormone replacement. The practical takeaway is clear: bone health in Turner syndrome requires more than tweaking the dose or the route of oestrogen — it means monitoring vitamin D status and keeping up regular DEXA surveillance. This is, after all, a retrospective pilot study with a small number of participants, so its findings should be read as a signal for larger research rather than a definitive recommendation.
Source: Transdermal versus oral hormone replacement therapy and bone mass density in Turner syndrome patients: a pilot study. Widmann K, Hager M, Windischbauer LM, Krysiak R, Ott J. Gynecological Endocrinology 2026;42(2692740). DOI: 10.1080/09513590.2026.2692740.
Read the publication: https://doi.org/10.1080/09513590.2026.2692740 (PubMed: 42351362).
