The Effect of Oxytocin (OT) and Oxytocin Plus Human Chorionic Gonadotropin (hCG), in Cycles Induced by Letrozole or Clomiphene Citrate
Condition: Ovarian Response
Study type: Interventional
Phase: Phase 2

Summary: 
      The specific aims of this study were to assess whether letrozole as an aromatase inhibitor
      plus hCG or OT alone, or in combination compared with CC, improves ovarian response.Ethical
      design of this study is based on the ethical guidelines of the Iranian Medical and Health
      Ministry which is accepted by Tabriz medical university ethical committee .
    

Detailed description: 
      In a randomized controlled prospective clinical study, a total of 177 infertile women with
      CC+hCG-resistant PCOS included. The candidates were selected for this study in the clinics of
      Tabriz University of Medical Sciences, East Azarbayejan Province, North West of Iran, from
      Oct. 2006 to Sep. 2007. Infertile women who had chronic anovulation and classical PCOS with
      CC+hCG failure were age <40 y , had patent tubes on hysterosalpingography, and no other
      pelvic pathology, participated in this study. The patients who had hypersensivity to any
      oxytocic medications, history of cardiovascular disease, and took anti-hypertensive
      medications were excluded. In addition, women with blood pressure less than 90/60 mmHg,
      abnormal spermogram, anxiety, excess prolactin levels, and other causes of infertility were
      excluded. All participants were given adequate information, and consent was obtained from
      each participant.

      The candidates were randomly divided into five groups including; letrozole + hCG (36
      patients) (group 1), letrozole + OT (35 patients) (group 2), letrozole +OT + hCG (35
      patients) (group 3), CC + OT (35 patients) (group 4), and CC + OT + hCG (36 patients) (group
      5). Participants received letrozole 2.5mg at first month and 5mg at the second and third
      month. Also, CC was used 50 mg at the first month, to 150 mg at the third month to stimulate
      follicular growth. Oxytocin (OXYTIP; manufactured by IPDIC, Rasht, Iran), 5 IU and hCG
      (Choriomon; manufactured by IBSA Institute Biochimique SA, CH-6903 Lugano), 5000 IU were also
      administrated to induce ovulation. All patients underwent transvaginal sonography on day 13
      to document the numbers of follicles and endometrial thickness. Participants were evaluated
      for three courses of intervention. Oxytocin was injected intramuscularly after CC or letrozol
      stimulation had induced enlarged ovarian follicles ( >18 mm in diameter to 30 mm). Decision
      to give a 5 IU dose of OT was made according to the pilot study (30). The patients who had
      larger follicles (more than 30mm in diameter), were withdrawn. The patients, who achieved
      pregnancy at the first or second month, were also withdrawn. All participants were evaluated
      for the levels of plasma progesterone one week after the injection of OT, hCG, or combination
      of them. A follow-up visit was arranged for each group every month at the second day of
      menstruation until 3 months after recruitment or at any time during the trial if pregnancy
      was achieved.
    

Intervention name(s): letrozole , oxytocin,hCG,clomiphene citrate
Intervention type(s): Drug
Intervention MeSH terms: Letrozole; Oxytocin; Clomiphene; Enclomiphene; Zuclomiphene
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Treatment
Keywords: Oxytocin; Letrozole; Induction of ovulation