title: Comparison of clinical characteristics between early and late patterns in hospitalized patients with ovarian hyperstimulation syndrome.
abstract: OBJECTIVE
  To clarify the differences in clinical characteristics between early and late ovarian hyperstimulation syndrome (OHSS).
  
  
  METHODS
  Retrospective study.
  
  
  METHODS
  Tertiary university hospital.
  
  
  METHODS
  Ninety-four patients/cycles hospitalized for moderate-to-severe OHSS after controlled ovarian hyperstimulation (COH) for IVF/intracytoplasmic sperm injection (ICSI); early type (n = 69) and late type (n = 25).
  
  
  METHODS
  None.
  
  
  METHODS
  The COH and pregnancy outcomes, preclinical and clinical miscarriage rate, and hospital courses.
  
  
  RESULTS
  Serum E(2) levels (4,955.5 +/- 3,268.5 pg/mL vs. 2,340.8 +/- 960.6 pg/mL) and the number of follicles > or =11 mm on day of hCG administration (15.9 +/- 6.0 vs. 13.0 +/- 4.0), and the number of oocytes retrieved (21.9 +/- 9.7 vs. 13.2 +/- 5.9) were significantly higher in the early OHSS group compared with the late OHSS group. Clinical pregnancy rate (PR) was significantly higher in the late OHSS group (23.6% [13/55] vs. 92.0% [23/25]). There were no significant differences in multiple PR and disease severity between the two groups.
  
  
  CONCLUSIONS
  Early OHSS is associated with excessive ovarian response to gonadotropin stimulation, whereas late OHSS is closely associated with conception cycle. Our findings do not support that late OHSS is more severe and closely associated with multiple pregnancies compared with early OHSS.
authors.affiliation: Department of Obstetrics and Gynecology, College of Medicine, Seoul National University, Seoul 110-744, South Korea.
authors.forename: Kyung Hee
authors.initials: KH
authors.lastname: Lee
authors.forename: Seok Hyun
authors.initials: SH
authors.lastname: Kim
authors.forename: Byung Chul
authors.initials: BC
authors.lastname: Jee
authors.forename: Yong Jin
authors.initials: YJ
authors.lastname: Kim
authors.forename: Chang Suk
authors.initials: CS
authors.lastname: Suh
authors.forename: Ki Chul
authors.initials: KC
authors.lastname: Kim
authors.forename: Won Don
authors.initials: WD
authors.lastname: Lee
mesh_terms: D000328:Adult; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D016471:Ovarian Hyperstimulation Syndrome / Q000145:classification* / Q000150:complications* / Q000453:epidemiology / Q000209:etiology; D010062:Ovulation Induction / Q000009:adverse effects / Q000379:methods; D011247:Pregnancy; D011256:Pregnancy Outcome; D015995:Prevalence; D027724:Reproductive Techniques, Assisted / Q000009:adverse effects; D012189:Retrospective Studies; D012307:Risk Factors; D012720:Severity of Illness Index; D013997:Time Factors