title: Maternal magnesium sulphate exposure predicts neonatal magnesium blood concentrations.
abstract: Tocolytic use of magnesium sulphate is associated with excess neonatal mortality and has been proposed to follow a dose-response relationship. This study aimed to define the correlation between maternal and neonatal magnesium blood concentrations. Magnesium blood concentrations were retrospectively obtained for mother-neonate pairs who were cared for at an Intermountain Healthcare facility from January 2009 to October 2011. Complete data were available for 231 mother-neonate pairs. Mean (±SD) maternal and neonatal magnesium concentrations were 5.43±1.69 and 2.98±0.94 mg/dL, respectively. Maternal and neonatal magnesium concentrations were highly correlated (p<0.001). In univariate analyses, residual unexplained variability was high (r2=0.19). However, further multivariate analyses revealed that caesarian section, severe pre-eclampsia and Apgar score at 5 min. were significantly associated with neonatal magnesium concentrations (p<0.05 for all). Maternal magnesium concentrations correlate with neonatal exposure. This finding suggests that maternal monitoring deserves further evaluation as a marker of foetal toxicity.
authors.affiliation: Division of Clinical Pharmacology, Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, Utah, USA.
authors.forename: Catherine M T
authors.initials: CM
authors.lastname: Sherwin
authors.forename: Alfred
authors.initials: A
authors.lastname: Balch
authors.forename: Sarah C
authors.initials: SC
authors.lastname: Campbell
authors.forename: Jeunesse
authors.initials: J
authors.lastname: Fredrickson
authors.forename: Erin A S
authors.initials: EA
authors.lastname: Clark
authors.forename: Michael
authors.initials: M
authors.lastname: Varner
authors.forename: Chris
authors.initials: C
authors.lastname: Stockmann
authors.forename: E Kent
authors.initials: EK
authors.lastname: Korgenski
authors.forename: Joshua L
authors.initials: JL
authors.lastname: Bonkowsky
authors.forename: Michael G
authors.initials: MG
authors.lastname: Spigarelli
mesh_terms: D061605:Administration, Intravenous; D000328:Adult; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D016014:Linear Models; D008278:Magnesium Sulfate / Q000008:administration & dosage* / Q000097:blood*; D018811:Maternal Exposure; D015999:Multivariate Analysis; D011225:Pre-Eclampsia / Q000517:prevention & control; D011247:Pregnancy; D011256:Pregnancy Outcome; D011297:Prenatal Exposure Delayed Effects / Q000097:blood*; D012189:Retrospective Studies; D015149:Tocolytic Agents / Q000008:administration & dosage / Q000009:adverse effects / Q000097:blood; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D015149:Tocolytic Agents; D008278:Magnesium Sulfate