title: [Ovarian hyperstimulation syndrome in a spontaneous pregnancy].
abstract: BACKGROUND
  Ovarian hyperstimulation syndrome (OHSS) is considered to be an iatrogenic complication of ovulation induction therapy. However, OHSS may rarely be associated with spontaneous ovulatory cycles, usually in multiple or molar gestations or hypothyroidism. Clinical manifestations vary and may be potentially fatal in severe cases.
  
  
  METHODS
  A 28-year-old primigravid, with no history of an infertility treatment, presented with enlarged ovaries and ascite. The patient had minor abdominal discomfort, without other complains. Ultrasound evaluation showed enlarged cystic ovaries and mild ascites. Hormonal profile revealed increased estradiol levels, with normal TSH and hCG. The patient was managed expectantly with no complications.
  
  
  CONCLUSIONS
  Although spontaneous OHSS is a rare entity, it is important to consider it in cases of bilateral ovarian masses in pregnancy. Three different mechanisms responsible for the occurrence of spontaneous OHSS have been described. This syndrome is thought to be secondary to promiscuity of the FSH receptor for hCG and/or TSH. It may occur with normal or increased levels of hCG and/or TSH.
authors.affiliation: Serviço de Ginecologia / Obstetrícia. Maternidade Dr. Alfredo da Costa, Lisbon, Portugal.
authors.forename: Carla
authors.initials: C
authors.lastname: Francisco
authors.forename: Catarina
authors.initials: C
authors.lastname: Júlio
authors.forename: Graça
authors.initials: G
authors.lastname: Pinto
authors.forename: Ana Teresa
authors.initials: AT
authors.lastname: Martins
authors.forename: Amadeu
authors.initials: A
authors.lastname: Ferreira
authors.forename: Luísa
authors.initials: L
authors.lastname: Martins
mesh_terms: D000328:Adult; D006063:Chorionic Gonadotropin / Q000097:blood; D004958:Estradiol / Q000097:blood; D005260:Female; D006801:Humans; D016471:Ovarian Hyperstimulation Syndrome / Q000097:blood / Q000000981:diagnostic imaging / Q000209:etiology*; D011247:Pregnancy; D011248:Pregnancy Complications / Q000097:blood; D035583:Rare Diseases / Q000097:blood / Q000000981:diagnostic imaging / Q000209:etiology*; D013972:Thyrotropin / Q000097:blood; D014463:Ultrasonography
chemical_list: D006063:Chorionic Gonadotropin; D004958:Estradiol; D013972:Thyrotropin