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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 ?
Relaxin loosens muscles and ligaments in preparation for childbirth.
My used to "My body was used to being like a stiff, coiled spring so the relaxin really affected me," said Jessica, who lives in Sheffield with her husband Andy and their two children - Reggie, who's now four, and Olivia, 20 months.
Whereas, some substances can cause endocrine system disorder, which is mainly induced by estrogen, relaxin, or glycometabolism, and some other substances can cause behavioral responses in MCF7 cells on exposure to addictive substances.
Rocco et al., "Relaxin stimulates expression of vascular endothelial growth factor in normal human endometrial cells in vitro and is associated with menometrorrhagia in women," Human Reproduction, vol.
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 hormones secreted by the placenta are human chorionic gonadotropin, human chorionic somatomammotropins, human chorionic thyrotropin, placental progesterone, placental estrogen, and relaxin. [2] Other placental hormones include corticotropin-releasing hormone, endorphins, dynorphins, gonadotropin-releasing hormones, inhibin, leptin, prolactin, and prorenin.
The product is a relaxin receptor agonist and recombinant form of the naturally-occurring human relaxin-2 hormone.
The thirteenth edition updates immunization schedules and current knowledge on moles, stress fractures, fasting blood sugar values, blood pressure factors, digestive disorders, trans fat, weight loss surgery, overactive bladder, hormone relaxin, cervical cancer testing, and cystic fibroids.
(3) Its receptor, relaxin family peptide 2 (RXFP2 gene), is expressed on the gubernaculum.
Estrogen and relaxin give strength and flexibility to the ligaments.
Others support the theory that the hormone relaxin which affects the ligaments of the pelvic girdle as the cause of low back pain even this also has not been shown by researchers as a cause of low back pain in pregnant women (Vleeming, Albert, Ostgaad, Sturesson, & Stuge, 2008).
In the Relaxin in Acute Heart Failure trial (RELAX-AHF) in patients with acute decompensated HF, GDF-15 decreased from admission to day 14 as the patients' clinical status gradually improved (72).