title: [Superfetation: case report and review of the literature].
abstract: We report the case of a dichorionic-diamniotic pregnancy in which a discordance in the size of the fetuses was observed as early as the first trimester. This discordance in size was maintained over time and the two fetuses continued their respective growths. We suggest the very rare phenomenon of superfetation as a diagnosis because less than 10 cases are described in the literature. Even though a formal proof of the diagnosis is difficult to obtain, the elements described in this article rally in favor of this hypothesis. Superfetation is defined by the fertilization and the implantation of a second oocyte in a uterus already containing the product of a previous conception. After a description of the case, a review of the literature enables us to describe the frequency, the possible risk factors and the existing case reports on the subject. The rarity of this case justifies its publication for the information of clinicians.
authors.affiliation: Service de gynécologie-obstétrique, médecine foetale et de la reproduction, hôpital mère-enfant, 38, boulevard Jean-Monnet, 44093 Nantes cedex 1, France.
authors.forename: O
authors.initials: O
authors.lastname: Pape
authors.forename: N
authors.initials: N
authors.lastname: Winer
authors.forename: A
authors.initials: A
authors.lastname: Paumier
authors.forename: H-J
authors.initials: HJ
authors.lastname: Philippe
authors.forename: B
authors.initials: B
authors.lastname: Flatrès
authors.forename: G
authors.initials: G
authors.lastname: Boog
mesh_terms: D000328:Adult; D005260:Female; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D011247:Pregnancy; D011256:Pregnancy Outcome; D011261:Pregnancy Trimester, First; D012307:Risk Factors; D013476:Superfetation / Q000502:physiology*; D014429:Twins, Dizygotic; D016216:Ultrasonography, Prenatal