title: Excessive ovarian response is associated with increased expression of interleukin-2 in the periimplantation endometrium.
abstract: OBJECTIVE
  To evaluate and compare in vivo expression of T helper type 1 (Th1) cytokines in the peri-implantation endometrium of infertile patients between natural and stimulated cycles.
  
  
  METHODS
  An observational study.
  
  
  METHODS
  A tertiary assisted reproduction center.
  
  
  METHODS
  Infertile patients.
  
  
  METHODS
  Uterine flushings and endometrial biopsies were collected 7 days after LH surge in natural cycles or after hCG injection in stimulated cycles.
  
  
  METHODS
  T helper type 1 cytokines were determined by immunolocalization and by ELISA.
  
  
  RESULTS
  Natural cycles were classified as group A (n = 17), whereas stimulated cycles with peak serum E(2) of <or=20,000 pmol/L (moderate responders) and with peak serum E(2) of >20,000 pmol/L (excessive responders) were classified as group B (n = 32) and group C (n = 32), respectively. Higher serum E(2) concentration was associated with increased expressions of interleukin (IL)-2 in the endometrium and uterine flushing. Group C demonstrated a statistically significantly higher IL-2 expression in endometrial biopsies by glandular and stromal immunostaining and by ELISA, compared with group A and group B. There was no difference in IL-2 concentration between group A and group B. Interferon-gamma protein concentration was comparable for the three groups.
  
  
  CONCLUSIONS
  Increased expression of IL-2 in the peri-implantation endometrium may account for the lower implantation rate in excessive responders.
authors.affiliation: Department of Obstetrics and Gynecology, The University of Hong Kong, Hong Kong, People's Republic of China.
authors.forename: Guneet
authors.initials: G
authors.lastname: Makkar
authors.forename: Ernest Hung Yu
authors.initials: EH
authors.lastname: Ng
authors.forename: William Shu Biu
authors.initials: WS
authors.lastname: Yeung
authors.forename: Pak Chung
authors.initials: PC
authors.lastname: Ho
mesh_terms: D000328:Adult; D001706:Biopsy; D010064:Embryo Implantation / Q000502:physiology*; D004717:Endometrium / Q000378:metabolism* / Q000473:pathology; D005260:Female; D006801:Humans; D007247:Infertility, Female / Q000378:metabolism* / Q000473:pathology; D007371:Interferon-gamma / Q000378:metabolism; D007376:Interleukin-2 / Q000378:metabolism*; D016471:Ovarian Hyperstimulation Syndrome / Q000378:metabolism*; D011247:Pregnancy; D018873:Pregnancy Rate; D006377:T-Lymphocytes, Helper-Inducer / Q000378:metabolism; D007507:Therapeutic Irrigation; D014599:Uterus / Q000473:pathology
chemical_list: C508594:IL2 protein, human; D007376:Interleukin-2; D007371:Interferon-gamma