title: Maternal obesity and its relationship with spontaneous and oxytocin-induced contractility of human myometrium in vitro.
abstract: Maternal obesity is associated with increased rates of labor induction, dysfunctional labor requiring intrapartum cesarean delivery, and postpartum hemorrhage, implying that maternal obesity has an inhibitory effect on myometrial function and its ability to respond to oxytocin. This study aimed to use an in vitro model to investigate the relationship between maternal body mass index (BMI) and the ability of myometrium to contract spontaneously and in response to oxytocin. Linear mixed effects regression modeling was applied to contractile data from 609 strips from 85 women. No correlation was found between maternal BMI and any indices of spontaneous myometrial activity. A single addition of oxytocin increased contractility, however, this was not related to maternal BMI. Similarly, oxytocin concentration-response curves were unrelated to BMI. Overall, the results from this in vitro study suggest that the observed implications of obesity on parturition in vivo cannot be explained by a direct effect on myometrial contractile mechanisms per se.
authors.affiliation: Reproductive & Maternal Medicine, Faculty of Medicine, University of Glasgow, United Kingdom. c.higgins@clinmed.gla.ac.uk
authors.forename: Claire A
authors.initials: CA
authors.lastname: Higgins
authors.forename: William
authors.initials: W
authors.lastname: Martin
authors.forename: Laurie
authors.initials: L
authors.lastname: Anderson
authors.forename: Andrew M
authors.initials: AM
authors.lastname: Blanks
authors.forename: Jane E
authors.initials: JE
authors.lastname: Norman
authors.forename: A
authors.initials: A
authors.lastname: McConnachie
authors.forename: S M
authors.initials: SM
authors.lastname: Nelson
mesh_terms: D000328:Adult; D001706:Biopsy; D015992:Body Mass Index; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D066298:In Vitro Techniques; D016014:Linear Models; D009215:Myometrium / Q000166:cytology / Q000502:physiology*; D009765:Obesity / Q000503:physiopathology*; D010121:Oxytocin / Q000494:pharmacology*; D011247:Pregnancy; D011248:Pregnancy Complications / Q000503:physiopathology*; D014590:Uterine Contraction / Q000187:drug effects* / Q000502:physiology*; D055815:Young Adult
chemical_list: D010121:Oxytocin