title: Luteal blood flow in patients undergoing GnRH agonist long protocol.
abstract: BACKGROUND
  Blood flow in the corpus luteum (CL) is closely related to luteal function. It is unclear how luteal blood flow is regulated. Standardized ovarian-stimulation protocol with a gonadotropin-releasing hormone agonist (GnRHa long protocol) causes luteal phase defect because it drastically suppresses serum LH levels. Examining luteal blood flow in the patient undergoing GnRHa long protocol may be useful to know whether luteal blood flow is regulated by LH.
  
  
  METHODS
  Twenty-four infertile women undergoing GnRHa long protocol were divided into 3 groups dependent on luteal supports; 9 women were given ethinylestradiol plus norgestrel (Planovar) orally throughout the luteal phase (control group); 8 women were given HCG 2,000 IU on days 2 and 4 day after ovulation induction in addition to Planovar (HCG group); 7 women were given vitamin E (600 mg/day) orally throughout the luteal phase in addition to Planovar (vitamin E group). Blood flow impedance was measured in each CL during the mid-luteal phase by transvaginal color-pulsed-Doppler-ultrasonography and was expressed as a CL-resistance index (CL-RI).
  
  
  RESULTS
  Serum LH levels were remarkably suppressed in all the groups. CL-RI in the control group was more than the cutoff value (0.51), and only 2 out of 9 women had CL-RI values < 0.51. Treatments with HCG or vitamin E significantly improved the CL-RI to less than 0.51. Seven of the 8 women in the HCG group and all of the women in the vitamin E group had CL-RI < 0.51.
  
  
  CONCLUSIONS
  Patients undergoing GnRHa long protocol had high luteal blood flow impedance with very low serum LH levels. HCG administration improved luteal blood flow impedance. This suggests that luteal blood flow is regulated by LH.
authors.affiliation: Department of Obstetrics and Gynecology, Yamaguchi University Graduate School of Medicine, Minamikogushi 1-1-1, Ube, 755-8505, Japan. sugino@yamaguchi-u.ac.jp.
authors.forename: Akihisa
authors.initials: A
authors.lastname: Takasaki
authors.forename: Isao
authors.initials: I
authors.lastname: Tamura
authors.forename: Fumie
authors.initials: F
authors.lastname: Kizuka
authors.forename: Lifa
authors.initials: L
authors.lastname: Lee
authors.forename: Ryo
authors.initials: R
authors.lastname: Maekawa
authors.forename: Hiromi
authors.initials: H
authors.lastname: Asada
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Taketani
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Tamura
authors.forename: Katsunori
authors.initials: K
authors.lastname: Shimamura
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Morioka
authors.forename: Norihiro
authors.initials: N
authors.lastname: Sugino