Thyroid hormones modify uterine contractility | 14761
Endocrinology & Metabolic Syndrome

Endocrinology & Metabolic Syndrome
Open Access

ISSN: 2161-1017

Thyroid hormones modify uterine contractility

World Congress on Endocrinology

August 26-28, 2013 DoubleTree by Hilton, Raleigh, NC, USA

Stephanie Corriveau

Scientific Tracks Abstracts: Endocrinol Metab Synd

Abstract :

To date, no study has evaluated whether uterine contractility is modified by hypothyroidism or T 4 treatment. This study analyzes the physiological role of Levothyroxine (T 4 ) and Triiodothyronine (T 3 ) on uterine contractions. Three approaches were used to assess our objectives. Human model . Uterine biopsies were obtained from consenting female patients undergoing elective caesarean under T 4 treatment compared to control patients (N=26). Animal model . To induce hypothyroidism, Sprague- Dawley rats (N=18) followed an iodine deficient diet in absence or in presence of high doses of T 4 (100 ng/kg/day). Isometric tension measurements were performed in vitro on myometrium tissues in isolated organ baths to evaluate the contractile activities using various pharmacological tools. Epidemiological approach . With the aim of extending our in vitro observations, an institutional database was screened to perform a retrospective analysis of pregnancy outcomes on a cohort of 8638 women. On uterine strips from women treated for hypothyroidism, we observed phasic contractions of larger amplitude (+ 77%), with a prolonged duration at 90% relaxation (+ 138%) and reduced frequency (- 55%) as compared to the values from the control group. In the animal model, we demonstrated that hypothyroidism significantly decreases contractile duration, and increase the contractile frequency while high doses of T 4 increases duration and decreases frequency. These results mimic the pattern of abnormal contractions observed in T 4 -treated pregnant women. Upon epidemiological review, the C-section rate was two-fold higher in this group. Thus, a better management of patients is required during pregnancy to reduce the C-section rate in this group.

Biography :

Stephanie Corriveau is a Ph.D. student from Universit� de Sherbrooke (Qu�bec, Canada). Her work focuses on the prevention of preterm labor and more specifically, on the inhibition of myometrial contractile activity. She has already published 5 articles in international journals, among which an original observation in the Am J. of Physiol. Endocrinology and metabolism . She is a recipient of Ph.D. bursaries from both FRQS (Fond de Recherche du Qu�bec-Sant�) and Rx & D Health Research Foundation. She is the recipient of several awards from the Foundation of Stars, Club de Recherches Cliniques du Qu�bec and the Universit� de Sherbrooke Faculty of Medicine and Health Sciences.