One month of hormone replacement therapy caused Menarche in primary ovarian insufficiency

A report describes a case of a 17-year-old Taiwanese female who presented to the gynecology clinic with complaints of primary amenorrhea and the absence of secondary sexual characteristics. 

She displayed a height of 158.8 cm (40th percentile), a weight of 45 kg (10th percentile), a body mass index of 17.8 (normal range: 17.7–22.7), and normal intelligence. Her parents had a mid-parental height estimate as 156 cm +/− 7 cm, and she was born of consanguineous marriage with normal developmental milestones. 

Physical examination revealed no significant cardiovascular, respiratory, or central nervous system findings. The patient had pubic and axillary hair but no breast bud development (Tanner stage B1PH3). Her external genitalia was underdeveloped. Greulich and Pyle's method estimated her bone age as 13 years. 

Her pelvic ultrasonography and magnetic resonance imaging (MRI) revealed the absence of the uterus and vaguely visible bilateral ovaries. Laboratory investigation documented high random follicular-stimulating hormone/luteinizing hormone and estrogen levels suggesting poor ovarian function. Her Prolactin levels and renal and thyroid functions were normal. 

In the pediatric endocrinology clinic, her hormonal levels and Karyotype of a normal female 46, XX genotype were confirmed. She received an initial diagnosis of ovarian agenesis and primary ovarian insufficiency (POI). 

A bone marrow density with dual-energy X-ray absorptiometry (DXA) skeletal survey assessment for osteoporosis documented a Z-score of − 2.7. The patient and family obtained comprehensive fertility counsel, and the patient received hormone replacement therapy (HRT) with oral conjugated estrogen (0.625 mg/tablet) for secondary sexual characteristics development and bone health restoration.

After a month of therapy, the patient experienced breakthrough bleeding. Follow-up pelvic ultrasonography documented a visible uterus, and physical examination confirmed breast bud development. Hence, she received a diagnosis of Primary ovarian insufficiency and therapy of oral estrogen (conjugated estrogen 0.625 mg) with progesterone (medroxyprogesterone 5 mg). 

After one year of hormonal replacement therapy, her bone marrow density and bone age maturation improved. Her latest sonography reported a mature uterus with the continued development of secondary sex characteristics (Tanner stage B3Ph3) and regular menstruation.

Cheng B. Menarche in primary ovarian insufficiency after a month of hormone replacement therapy: a case report. J Med Case Reports.2021; 15. https://doi.org/10.1186/s13256-020-02603-6