title: The effect of routine magnesium supplementation on fetal cardiac time intervals: a fetal magnetocardiographic study.
abstract: OBJECTIVE
  Magnesium deficiency in pregnancy is frequent, and in consequence magnesium supplementation is widely used. As magnesium crosses the placental barrier and since the fetal kidney does not excrete magnesium as efficiently as the mature kidney, effects on fetal cardiac time intervals are probable, but still unknown.
  
  
  METHODS
  Sixty pregnant women were included in an observational study: 31 patients received oral routine magnesium supplementation. In addition to routine fetal echocardiography, fetal magnetocardiography (fMCG) was used to investigate electrophysiological rhythm patterns with high temporal resolution. fMCG tracings were analyzed according to a predefined procedure for fetal cardiac time interval (CTI)-detection. fCTI findings (P-wave, PQ-segment, PR-interval, QRS complex, ST segment, T-wave and QTc interval) were registered.
  
  
  RESULTS
  Significant widening of the QRS-complex (p=0.004) was demonstrated in fetuses whose mothers received magnesium supplementation (240 mg/day) relative to the control group.
  
  
  CONCLUSIONS
  Magnesium exposed fetuses demonstrated a prolonged ventricular arousal, but healthy neonatal outcome was found in all exposed fetuses. Although fMCG is a preclinical method and limited in its availability, the procedure could help to monitor fetuses.
authors: Department of Neonatology, University Children's Hospital Tübingen, Germany. annette.wacker@med.uni-tuebingen.de
authors: Annette
authors: A
authors: Wacker-Gußmann
authors: Johanna
authors: J
authors: Brändle
authors: Magdalene
authors: M
authors: Weiss
authors: Jana
authors: J
authors: Muenssinger
authors: Anne
authors: A
authors: Zimmermann
authors: Harald
authors: H
authors: Abele
authors: Rangmar
authors: R
authors: Goelz
authors: Hubert
authors: H
authors: Preissl
mesh_terms: D000328:Adult; D001724:Birth Weight; D019587:Dietary Supplements / Q000009:adverse effects*; D005260:Female; D006352:Heart Ventricles / Q000196:embryology / Q000503:physiopathology*; D006801:Humans; D050498:Live Birth; D017616:Magnesium Compounds / Q000009:adverse effects* / Q000627:therapeutic use; D008275:Magnesium Deficiency / Q000517:prevention & control*; D053798:Magnetocardiography; D039382:Maternal Nutritional Physiological Phenomena; D011247:Pregnancy; D011248:Pregnancy Complications / Q000517:prevention & control*; D011256:Pregnancy Outcome; D011262:Pregnancy Trimester, Second; D011263:Pregnancy Trimester, Third; D011296:Prenatal Diagnosis; D012720:Severity of Illness Index; D014693:Ventricular Fibrillation / Q000196:embryology / Q000209:etiology* / Q000503:physiopathology; D055815:Young Adult
chemical_list: D017616:Magnesium Compounds