Endocrine Abstracts

JOINT3476

Objective: Individuals with Turner syndrome (TS) often require estrogen replacement therapy (ERT) for pubertal induction. However, data on the optimal replacement regimen and effects on uterine growth are limited. This study aims to evaluate the impact of different routes of ERT on uterine dimensions in individuals with TS.

Methods: This is a single-center, cross-sectional study. It included 19 individuals with TS aged 15–30 (median age:22. 3) years who had undergone pubertal induction with transdermal (n = 15, initiation dose of 6. 25 mg/day) or oral 17β-estradiol (n = 4, initiation dose of 0. 25 mg/day) preparations, and 20 healthy controls (median age:21. 5 years). Uterine length, fundal transverse diameter, fundal anteroposterior diameter, cervical anteroposterior diameter, fundal-cervical ratio (FCR), endometrial thickness, and uterine volume were assessed by transabdominal pelvic ultrasonography. Anthropometric measurements, karyotype, laboratory data, and treatment information were obtained from existing patient records. Those who discontinued ERT after the transition to adult clinics (n = 5) were considered non-adherent. The TS group was divided into subgroups according to ERT route (transdermal, 17β-estradiol), treatment adherence (adherent, non-adherent) and karyotype characteristics (45, X=classic, karyotypes other than 45, X=non-classic).

Results: The median height in the TS group was 152 (range:147–161) cm, and the median BMI was 24. 6 (range:17. 8–42. 5) kg/m². The median age at initiation of pubertal induction was 13. 5 (range:12. 0–15. 7) years. Uterine volume was significantly lower in the TS group compared to the control group (P < 0. 001); however, in those who underwent pubertal induction with transdermal estrogen, uterine length was not significantly different from the control group (P = 0. 194). The oral 17β-estradiol group had significantly lower fundal anteroposterior diameter and uterine volume than the transdermal group (P = 0. 021 and P = 0. 028, respectively). Except for the FCR, all uterine dimensions were significantly lower in the non-adherent group compared to those with adherent. There were no statistically significant differences in uterine dimensions between the karyotype groups. Growth hormone therapy (GHT) was administered to 94. 7% (n = 18) of individuals with TS. A moderate, statistically significant positive correlation was found between duration of GHT and uterine volume (r = 0. 518, P = 0. 023).

Conclusion: This study highlights the significant impact of the route of ERT for pubertal induction on uterine development in TS. Underlining the importance of adherence, non-adherent was associated with significantly smaller uterine dimensions. Although our sample size is limited, transdermal estrogen showed superior outcomes in uterine size development compared to oral 17β-estradiol. GH therapy does have a positive correlation with uterine length in both routes of ERT.