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Medical Term:


Pronunciation: re-lak'sin


A polypeptide hormone secreted by the corpora lutea of mammalian species during pregnancy. Facilitates the birth process by causing a softening and lengthening of the pubic symphysis and cervix; it also inhibits contraction of the uterus and may play a role in timing of parturition.

Synonym(s): cervilaxin, ovarian hormone, parturition-mediating factor, releasin

[relax + -in]

© Copyright 2017 Wolters Kluwer. All Rights Reserved. Review Date: Sep 19, 2016.