Analysis of secondary amenorrhea in reproductive age group: a prospective observational study

Background: Secondary amenorrhea is a clinically important and has diverse hypothalamic, pituitary, ovarian and endocrine causes. Identification of the underlying cause is essential as persistent anovulation may affect fertility and long-term health. The topic was undertaken due to the scarcity of data from central India. Objective was to identify the etiology and review the differential diagnosis of secondary amenorrhea among women of reproductive age. Methods: A prospective observational study was conducted in the department of obstetrics and gynecology, JLNHRC, Bhilai, Chhattisgarh, over 18 months. 72 women of reproductive age having secondary amenorrhea were enrolled. Patients with pregnancy, lactation, menopause or using Mirena or depot medroxyprogesterone acetate were excluded. Detailed clinical evaluation, UPT, CBC, serum TSH, serum prolactin, pelvic ultrasound and progesterone challenge test were performed. Etiological patterns and associations with BMI, lifestyle, stress and dietary habits were analysed. Results: The participants were between 16-35 years. 44 (61.1%) were unmarried. Among 28 married women, 17 had associated infertility. 44 (61.1%) were overweight or obese. PCOS was identified in 21 (29.2%), hypothyroidism in 16 (22.2%) and hyperprolactinemia in 6 (8.3%) women. In 33 (45.8%) no specific cause was identified by available preliminary evaluation and these were classified as probable functional hypothalamic amenorrhea (FHA). Among women with PCOS, BMI was significantly associated with diagnosis (p<0.001). Probable FHA showed significant associations with lifestyle (p=0.004), dietary habits (p=0.0026), BMI (p=0.015) and stress (p=0.028). Conclusions: Secondary amenorrhea has a heterogeneous etiology. A structured clinical assessment with basic laboratory investigations and pelvic ultrasonography can identify a substantial proportion of causes without immediately resorting to extensive hormonal testing. Obesity, lifestyle, dietary habits and psychological stress are modifiable, while persistent or atypical cases require further endocrine and structural evaluation.