title: Fetal ductal constriction caused by maternal ingestion of green tea in late pregnancy: an experimental study.
abstract: OBJECTIVE
  The aim of this study was to test the hypothesis that experimental maternal intake of green tea in late pregnancy causes fetal ductus arteriosus constriction, probably because of prostaglandin inhibition.
  
  
  RESULTS
  Twelve fetal lambs (pregnancy > 120 days) were assessed before and after maternal administration of green tea (n = 8) or water (n = 4; controls) as the only source of liquid. After 1 week, echocardiography showed signs of constriction of the ductus arteriosus in all fetuses from mothers ingesting green tea, with increase in mean systolic velocity(from 0.70 ± 0.19 m/s to 0.92 ± 0.15 m/s, 31.4%, p = 0.001) and mean diastolic velocity (0.19 ± 0.05 m/s to 0.31 ± 0.01 m/s, 63.1%, p < 0.001), decrease of pulsatility index (2.2 ± 0.4 to 1.8 ± 0.3, 22.2%, p = 0.003) and increase of mean right ventricular/left ventricular diameter ratio (0.89 ± 0.14 to 1.43 ± 0.23, 60.6%, p < 0.001). In the four control fetuses, there were no significant changes. All lambs exposed to green tea also showed at autopsy dilated and hypertrophic right ventricles, which was not present in control fetuses. Histological analysis showed a significantly larger mean thickness of the medial avascular zone of the ductus arteriosus in fetuses exposed to green tea than in controls (747.6 ± 214.6 µm vs 255.3 ± 97.9 µm, p < 0.001).
  
  
  CONCLUSIONS
  This study in fetal lambs shows a cause and effect relationship between experimental maternal exposure of green tea and fetal ductus arteriosus constriction in late pregnancy.
authors: Fetal Cardiology Unit, Instituto de Cardiologia do Rio Grande do Sul/FUC (IC/FUC), Porto Alegre, RS, Brazil. zielinsky@cardiol.br
authors: Paulo
authors: P
authors: Zielinsky
authors: João L L
authors: JL
authors: Manica
authors: Antonio L
authors: AL
authors: Piccoli
authors: Luiz Henrique S
authors: LH
authors: Nicoloso
authors: Marinez
authors: M
authors: Barra
authors: Marcelo M
authors: MM
authors: Alievi
authors: Izabele
authors: I
authors: Vian
authors: Ana
authors: A
authors: Zilio
authors: Patrícia E
authors: PE
authors: Pizzato
authors: Júlia S
authors: JS
authors: Silva
authors: Luciano P
authors: LP
authors: Bender
authors: Marcelo
authors: M
authors: Pizzato
authors: Honório S
authors: HS
authors: Menezes
authors: Solange C
authors: SC
authors: Garcia
mesh_terms: D000818:Animals; D003251:Constriction, Pathologic / Q000000981:diagnostic imaging / Q000473:pathology / Q000662:veterinary; D004373:Ductus Arteriosus / Q000000981:diagnostic imaging / Q000196:embryology* / Q000473:pathology; D005260:Female; D005865:Gestational Age; D023421:Models, Animal; D011247:Pregnancy; D011448:Prostaglandin Antagonists; D012756:Sheep / Q000196:embryology*; D013662:Tea / Q000009:adverse effects*; D016216:Ultrasonography, Prenatal / Q000662:veterinary
chemical_list: D011448:Prostaglandin Antagonists; D013662:Tea