The Impact of Hashimoto's Thyroiditis on the Menstrual Cycle in Adolescent Girls: A Clinical-Retrospective Analysis

Lala Azayli  

Abstract. Puberty represents a critical physiological window (ages 13–15) characterized by the maturation of the hypothalamic-pituitary-ovarian (HPO) axis. Hashimoto’s Thyroiditis (HT), the most prevalent autoimmune endocrine disorder in this demographic, poses a significant threat to reproductive stability. This retrospective study evaluates the correlation between elevated thyroid autoantibodies (anti-TPO, anti-TG) and menstrual irregularities in 13–15-year-old girls. During this stage, the thyroid gland's functional state is essential for the harmonious operation of the neuroendocrine system. Our data analysis reveals that secondary hyperprolactinemia and impaired sex-hormone metabolism, often secondary to subclinical hypothyroidism, are the primary drivers of menstrual dysfunction. In this clinical-retrospective study, we analyzed the endocrine profiles and menstrual calendars of adolescents diagnosed with HT compared to a healthy control group. The findings indicate that oligomenorrhea was identified in 45% of the HT cohort, a stark contrast to the 10‒12% observed in the control group. Furthermore, severe dysmenorrhea and menorrhagia were significantly more prevalent in patients with high anti-TPO titers. The results emphasize that the structural similarity between TSH and gonadotropins, along with the stimulatory effect of TRH on prolactin, creates a "hormonal storm" that disrupts ovulation. Early screening for autoimmune thyroid panels in adolescents with irregular cycles and timely initiation of hormone replacement therapy are paramount. This proactive approach holds significant prophylactic importance in preventing future reproductive sequelae, such as chronic anovulation and subfertility.

Keywords: hashimoto’s thyroiditis, adolescent health, menstrual irregularities, pediatric endocrinology, autoimmune thyroiditis, anti-tPO, oligomenorrhea, hpo axis, hyperprolactinemia