Calcium Carbonate Concretions: Cyclic Occurrence in the Hamster Vagina

See allHide authors and affiliations

Science  05 Nov 1971:
Vol. 174, Issue 4009, pp. 600-603
DOI: 10.1126/science.174.4009.600


Three crystalline forms of calcium carbonate were identified in washings of the hamster vagina. Spherical concretions of vaterite and hexagonal concretions of calcite predominate on days 3 and 4 of the 4-day estrous cycle. Dumbbell-like concretions of aragonite predominate during pregnancy and pseudopregnancy. Each polymorph is associated with an acid-insoluble matrix. Concretions disappear after ovariectomy and reappear during daily injections of estrogen and progesterone.