Unexplained amenorrhea in a patient taking methotrexate for the treatment of rheumatoid arthritis

The cause of secondary amenorrhea in the following case cannot be explained by traditional etiologies. We therefore questioned whether long-term methotrexate treatment played a role as an endometrial inhibitor.

A 44-year-old G4P2, with a 5-year history of rheumatoid arthritis, presented with a 2-year history of secondary amenorrhea. The patient took methotrexate since diagnosis. Her FSH, estrogen, prolactin, TSH and T4 levels were normal, her B-HCG was negative, her BMI was 22 and she had no history of Asherman's syndrome.

There is no information, based on our search, on whether long-term methotrexate treatment has an effect on the menstrual cycle. This case highlights the need for the elucidation of the effects of long-term methotrexate treatment on the menstrual cycle in patients with rheumatoid arthritis.