title: Arterio-arterial vascular anastomoses in monochorionic twin placentas with and without twin anemia-polycythemia sequence.
abstract: We performed a matched case-control study to analyze the placental angioarchitecture, in particular the diameter of arterio-arterial (AA) anastomoses in monochorionic placentas from pregnancies with spontaneous twin anemia-polycythemia sequence (TAPS) compared to a control group of uncomplicated monochorionic placentas. Placental angioarchitecture was analyzed using colored dye injection. AA anastomoses were detected in 20% (3/15) of spontaneous TAPS placentas. The median diameter of AA anastomoses in the group with and without TAPS was 0.4 mm and 2.2 mm, respectively (p = 0.01). In conclusion, AA anastomoses are rarely detected in TAPS placentas. When present, the AA anastomosis is very small, preventing equilibration of hemoglobin levels between both twins.
authors.affiliation: Division of Neonatology, Department of Pediatrics, J6-S, Leiden University Medical Center, P.O. Box 9600, 2300 RC Leiden, The Netherlands.
authors.forename: S
authors.initials: S
authors.lastname: de Villiers
authors.forename: F
authors.initials: F
authors.lastname: Slaghekke
authors.forename: J M
authors.initials: JM
authors.lastname: Middeldorp
authors.forename: F J
authors.initials: FJ
authors.lastname: Klumper
authors.forename: F J
authors.initials: FJ
authors.lastname: Walther
authors.forename: D
authors.initials: D
authors.lastname: Oepkes
authors.forename: E
authors.initials: E
authors.lastname: Lopriore
mesh_terms: D000740:Anemia / Q000209:etiology / Q000473:pathology*; D001159:Arterio-Arterial Fistula / Q000150:complications / Q000473:pathology*; D016022:Case-Control Studies; D002823:Chorion; D005260:Female; D005330:Fetofetal Transfusion / Q000150:complications / Q000209:etiology / Q000473:pathology; D005865:Gestational Age; D006801:Humans; D010920:Placenta / Q000098:blood supply / Q000473:pathology; D010922:Placenta Diseases / Q000209:etiology / Q000473:pathology*; D011086:Polycythemia / Q000209:etiology / Q000473:pathology*; D011247:Pregnancy; D059285:Pregnancy, Twin; D014430:Twins, Monozygotic; D014469:Umbilical Arteries / Q000002:abnormalities* / Q000473:pathology