title: Impact on fetal mortality and cardiovascular Doppler of selective ligature of uteroplacental vessels compared with undernutrition in a rabbit model of intrauterine growth restriction.
abstract: OBJECTIVE
  To compare the impact on birth weight, mortality and fetal haemodynamic changes of selective ligature of uteroplacental vessels vs maternal undernutrition as experimental models of intrauterine growth restriction in the pregnant rabbit.
  
  
  METHODS
  Three groups of NewZealand rabbit fetuses were compared: controls (n = 60), selective ligature of 40-50% of uteroplacental vessels (n = 38) and 70% diet restriction (n = 19), both starting at 25 days of gestation. Cardiovascular Doppler evaluation was performed before delivery in a subgroup of fetuses (15 controls and cases from surgical model and 10 fetuses from the undernutirtion model) before delivery including: umbilical artery pulsatility index (UAPI), middle cerebral artery pulsatility index (MCAPI), ductus venosus pulsatility index (DVPI), aortic isthmus pulsatility index (AoIPI), isovolumetric contraction time, ejection time, isovolumetric relaxation time (IRT), and myocardial performance index. Fetuses were delivered at 30 days of gestation by caesarean section and biometric measurements were recorded.
  
  
  RESULTS
  The mortality rate was significantly higher in the surgical group (54.2%) than in the undernutrition (5%) and control (14.3%) groups (p < 0.001). Changes of biometrical measurements increased across experimental groups, being more pronounced in the surgical model. Ultrasound evaluation demonstrated linear trend for increased values in DVPI (p = 0.003) and AoIPI (p = 0.029), and IRT (p = 0.003) across study groups, but statistically significant changes were only observed in the surgical model. No significant differences were observed in the UAPI or MCAPI.
  
  
  CONCLUSIONS
  While animal models fail to perfectly reproduce the human condition, selective ligature of uteroplacental vessels reproduces more closely cardiovascular features observed in human fetuses with intrauterine growth restriction when compared with undernutrition.
authors.affiliation: Department of Maternal-Fetal Medicine, Institut Clinic de Ginecologia, Obstetricia i Neonatologia, Hospital Clinic and Institut d'Investigacions Biomèdiques August Pi i Sunyer, University of Barcelona, Sabino de Arana 1, 08028 Barcelona, Spain.
authors.forename: E
authors.initials: E
authors.lastname: Eixarch
authors.forename: E
authors.initials: E
authors.lastname: Hernandez-Andrade
authors.forename: F
authors.initials: F
authors.lastname: Crispi
authors.forename: M
authors.initials: M
authors.lastname: Illa
authors.forename: I
authors.initials: I
authors.lastname: Torre
authors.forename: F
authors.initials: F
authors.lastname: Figueras
authors.forename: E
authors.initials: E
authors.lastname: Gratacos
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D005260:Female; D005317:Fetal Growth Retardation / Q000401:mortality*; D046689:Fetal Mortality; D008026:Ligation; D044342:Malnutrition / Q000503:physiopathology*; D010920:Placenta / Q000098:blood supply*; D011247:Pregnancy; D011248:Pregnancy Complications / Q000503:physiopathology*; D011817:Rabbits; D018608:Ultrasonography, Doppler; D016216:Ultrasonography, Prenatal