title: Maternal obesity affects fetal myocardial function as early as in the first trimester.
abstract: OBJECTIVE
  To investigate cardiac function from 14 weeks' gestation in fetuses of obese pregnant women (FOW). Animal studies have shown that maternal obesity induces fibrosis in fetal myocardium. We hypothesized that fetal cardiac function would be impaired among FOW.
  
  
  METHODS
  A case-control study with longitudinal follow-up was performed at Trondheim University Hospital, Norway. In total, 80 pregnant women were included and the final population comprised 52 obese and 24 of normal weight (mean body mass index before pregnancy, 34.8 ± 4.1 vs 21.0 ± 2.2 kg/m(2) ; P < 0.001). The main outcome measures were global strain rate (GSR) and strain by tissue Doppler imaging, tissue Doppler velocities (TDVs) and interventricular septal thickness assessed by fetal echocardiography at gestational ages of 14, 20 and 32 weeks.
  
  
  RESULTS
  In FOW, fetal left ventricle (LV) and right ventricle (RV) GSR and strain were significantly lower than in fetuses of normal-weight pregnant women: LV GSR was 33.3% lower at 14 weeks, 22.4% lower at 20 weeks and 22.8% lower at 32 weeks of gestation (P < 0.001) with no difference in fetal heart rate. Systolic and late diastolic TDVs for LV were significantly lower from 20 weeks' gestation and remained lower throughout pregnancy. Fetal interventricular septum was 26.6% (P < 0.001) thicker in late pregnancy in FOW compared with normal-weight pregnancies.
  
  
  CONCLUSIONS
  At 14 weeks of gestation, we detected fetal myocardial dysfunction with reduced LV and RV GSR and strain in FOW compared with fetuses of women with normal weight. Our finding is alarming considering the high prevalence of obesity and may partly explain the predisposition of offspring to cardiovascular disease later in life.
authors.affiliation: Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway.
authors.forename: C B
authors.initials: CB
authors.lastname: Ingul
authors.affiliation: National Center for Fetal Medicine, Department of Obstetrics and Gynecology, St. Olavs Hospital, Trondheim University Hospital, Trondheim, Norway.
authors.forename: L
authors.initials: L
authors.lastname: Lorås
authors.affiliation: National Center for Fetal Medicine, Department of Obstetrics and Gynecology, St. Olavs Hospital, Trondheim University Hospital, Trondheim, Norway.|Department of Laboratory Medicine, Children's and Women's Health, Norwegian University of Science and Technology, Trondheim, Norway.
authors.forename: E
authors.initials: E
authors.lastname: Tegnander
authors.affiliation: National Center for Fetal Medicine, Department of Obstetrics and Gynecology, St. Olavs Hospital, Trondheim University Hospital, Trondheim, Norway.|Department of Laboratory Medicine, Children's and Women's Health, Norwegian University of Science and Technology, Trondheim, Norway.
authors.forename: S H
authors.initials: SH
authors.lastname: Eik-Nes
authors.affiliation: National Center for Fetal Medicine, Department of Obstetrics and Gynecology, St. Olavs Hospital, Trondheim University Hospital, Trondheim, Norway.|Department of Laboratory Medicine, Children's and Women's Health, Norwegian University of Science and Technology, Trondheim, Norway.
authors.forename: A
authors.initials: A
authors.lastname: Brantberg
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D015150:Echocardiography, Doppler / Q000379:methods; D005260:Female; D005318:Fetal Heart / Q000000981:diagnostic imaging / Q000502:physiology*; D005500:Follow-Up Studies; D005865:Gestational Age; D006801:Humans; D008137:Longitudinal Studies; D009200:Myocardial Contraction / Q000502:physiology*; D009206:Myocardium; D009664:Norway; D009765:Obesity / Q000000981:diagnostic imaging / Q000503:physiopathology*; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D016216:Ultrasonography, Prenatal / Q000379:methods; D016276:Ventricular Function / Q000502:physiology
keywords: diastolic function; fetal cardiac function; fetal echocardiography; fetus; maternal obesity; strain rate; systolic function; tissue Doppler imaging