Endocrinological and ovarian histological investigations in assigned female at birth transgender people undergoing testosterone therapy.

RESEARCH QUESTION: What are the hormonal and ovarian histological effects of a gender affirming hormonal therapy in assigned female at birth (AFAB) transgender people?

DESIGN

Prospective observational study of 70 AFAB transgender people taking testosterone therapy before gender-affirming surgery (hystero-oophorectomy). A gynaecological ultrasonographic scan was undertaken and serum hormone concentrations measured, including anti-Müllerian hormone (AMH) and androgenic profile. Histological ovarian evaluation was assessed in both ovaries, including the developmental stages of the follicles.

RESULTS

The mean age of the population was 27.7+/-5.14 years. The main biochemical parameters were total testosterone levels 781.5 ± 325.9 ng/dl; AMH levels 3.2 ± 1.4 ng/ml; FSH and LH levels 4.9 ± 2.5 IU/l and 3.9 ± 2.9 IU/l, respectively; and oestradiol values 47.6 ± 13.7 pg/ml. Fifty-five AFAB underwent gynaecological ultrasound before surgery and antral follicles were found in 43 out of 47 ultrasounds (91.5%) (without the presence of a dominant follicle or corpus luteum). Histological follicles were mostly in the primordial stage (88.0) and 3.3% were atretic. The thickness of the tunica albuginea was widely heterogeneous (range 0.15-1.45 mm) and luteinization of the stromal cells was observed in 68.6% of the samples. A negative correlation between testosterone levels and total antral follicles was found (Rs= -0.306, P = 0.029).

CONCLUSIONS

AFAB transgender people taking testosterone therapy show cortical follicle distribution in the range previously reported in fertile cisgender women of reproductive age. The follicular population may not be altered as a result of the gender-affirming hormonal therapy, although some cortical and stromal changes have been observed.