The Natural History of Uterine Leiomyomas: Light and Electron Microscopic Studies of Fibroid Phases, Interstitial Ischemia, Inanosis, and Reclamation

Table 1

Fibroid Phases.

Phase	Estimated collagen content	Functional status
Phase 1	No, or insignificant, collagen matrix	Proliferation of myocytes
Phase 2	<10% collagen	Proliferation of myocytes, and synthesis of collagen
Phase 3	10–50% collagen	Proliferation, synthesis of collagen, and early senescence in late Phase 3
Phase 4	>50% collagen	Involution