title: [Relationship between letrozole administration during the luteal phase after oocyte retrieval and the early-stage ovarian hyperstimulation syndrome oocurrence].
abstract: OBJECTIVE
  To investigate the effect of letrozole in decreasing the early-stage ovarian hyperstimulation syndrome (OHSS) occurrence during the luteal phase for patients of OHSS high-risk after oocyte retrieval.
  
  
  METHODS
  A total of 176 high-risk OHSS patients were randomly divided into two groups after oocyte retrieval. Patients in experiment group (n = 86) received 5 mg letrozole per day from the retrieval day and last for 5 days. Others in control group (n = 90) received placebo. The serum concentration of FSH, LH, estradiol (E2), progesterone (P) and vascular endothelial growth factor (VEGF) from the day of hCG injection to days after injection (5 days, 8 days, 10 days) were measured. And the incidence of moderate and severe OHSS was observed.
  
  
  RESULTS
  The concentration of E2 on the indicated days (5 days, 8 days, 10 days after hCG injection) in experiment group and control group were (5 727±2 089) versus (11 826±4 281) pmol/L, (1 613±879) versus (7 925±3 507) pmol/L, (193± 90) versus (1 628±888) pmol/L; the concentration of VEGF on the indicated days in the two groups were (80±14) versus (108±19) ng/L, (66±11) versus (126±14) ng/L, (48±7) versus (148±14) ng/L; the concentration of E2 and VEGF were lower than those in control group (all P < 0.01). The FSH concentration in experiment group were (2.1±1.1) and (3.5±1.3) U/L on the day of fifth and eighth day after hCG injection, which were significantly higher than (0.7±0.3) and (0.7±0.4) U/L in control group (P < 0.05); the LH concentration in experiment group were (0.26±0.19) and (0.72±0.60) U/L on the day of fifth and eighth day after hCG injection, which were significantly higher than (0.11±0.03) and (0.14±0.08) U/L in control group (P < 0.05). The incidence of moderate and severe OHSS was signicantly decreased after letrozole treatment compared with control group [2% (2/86) versus 12% (11/90), P < 0.05].
  
  
  CONCLUSIONS
  Administration of 5 mg/d letrozole for 5 days during the luteal phase can reduce the E2 and VEGF levels for the high-risk OHSS patients who needed cryopreserve all embryos, and also reduce the occurrence of early OHSS.
authors.affiliation: Department of Reproductive Medicine, Henan Provincial People's Hospital, Zhengzhou 450003, China.
authors.forename: Qiaohua
authors.initials: Q
authors.lastname: He
authors.forename: Jianing
authors.initials: J
authors.lastname: Xu
authors.forename: Shihong
authors.initials: S
authors.lastname: Cui
authors.forename: Hangsheng
authors.initials: H
authors.lastname: Li
authors.affiliation: Email: 380870370@qq.com.
authors.forename: Cuilian
authors.initials: C
authors.lastname: Zhang
mesh_terms: D047072:Aromatase Inhibitors / Q000008:administration & dosage*; D004958:Estradiol / Q000097:blood; D005260:Female; D005307:Fertilization in Vitro; D006801:Humans; D007247:Infertility, Female / Q000628:therapy*; D000077289:Letrozole; D008183:Luteal Phase; D009570:Nitriles / Q000008:administration & dosage*; D054315:Oocyte Retrieval / Q000379:methods; D016471:Ovarian Hyperstimulation Syndrome / Q000097:blood / Q000517:prevention & control*; D011374:Progesterone / Q000097:blood; D014230:Triazoles / Q000008:administration & dosage*; D042461:Vascular Endothelial Growth Factor A / Q000097:blood
chemical_list: D047072:Aromatase Inhibitors; D009570:Nitriles; D014230:Triazoles; D042461:Vascular Endothelial Growth Factor A; D011374:Progesterone; D004958:Estradiol; D000077289:Letrozole