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A female hormone secreted by the corpus luteum that helps soften the cervix and relax the pelvic ligaments in childbirth.


1. (Biochemistry) a mammalian polypeptide hormone secreted by the corpus luteum during pregnancy, which relaxes the pelvic ligaments
2. (Pharmacology) a preparation of this hormone, used to facilitate childbirth
[C20: from relax + -in]


(rɪˈlæk sɪn)

a polypeptide hormone, produced by the corpus luteum during pregnancy, that causes the pelvic ligaments and cervix to relax during pregnancy and delivery.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.relaxin - hormone secreted by the corpus luteum during the last days of pregnancy; relaxes the pelvic ligaments and prepares the uterus for labor
endocrine, hormone, internal secretion - the secretion of an endocrine gland that is transmitted by the blood to the tissue on which it has a specific effect
References in periodicals archive ?
6] in their research, on serum relaxin in pregnancy, support the possibility of softening of suspensory ligaments of corneoscleral envelope due to hormone relaxin.
Furthermore, the use of agents known to facilitate parturition such as oxytocin or relaxin, after MPA administration, could overcome eventual alterations in expulsion of the fetuses.
The hormone relaxin is relaxing everything so it does make you more susceptible to overdoing things without even knowing it.
Learn more about the new heart failure drug relaxin.
Weight training - You will still have a hormone called relaxin flowing around your body, which makes the joints softer and more supple.
JosephwillwantCamelotto relaxin theearlystagesandI reckonhewill haveatleastfourorfivehorsesin frontofhimheadingdownthehill.
As the pelvic ligaments are relaxed or weakened during the birth process by relaxin and progesterone, there is more instability of the pelvic joints including pubic symphysis which sometimes lead to abnormal widening and injury followed by pain and disability.
The effects of relaxin could be another good possibility (22).
En el caso de Howard Florey / relaxin el hecho de que un cadn que codificaba H2-relaxin humana se habia aislado por primera vez y que este tipo de relaxin era diferente a la encontrada en la naturaleza (13).
Investigators tried to determine the earliest day of gestation at which relaxin--the only pregnancy-specific hormone reported in cats - could be detected in pregnant queens by using a commercially available point-of-care test designed for use in dogs ("Use of a commercially available relaxin test for detection of pregnancy in cats," Journal of the American Veterinary Medical Association, 2010).
Besides the fact that the left and right sides of your abs separate from one another (not the most comforting thought), your joints and ligaments loosen due to the pregnancy hormone relaxin.