Etiology

PALM-COEIN classification is used grouping causes into structural and non structural causes.

Structural causes

Polyps

Adenomyosis

Leiomyoma

Malignancy and hyperplasia

Non structural causes

Coagulopathy

Ovulatory dysfunction due to hypothyroidism, hyperthyroidism, prolactin-secreting tumors, PCOS

Endometrial

Iatrogenic (IUDs, chemotherapeutic agents, anticoagulants)

Not yet classified.