title: Dual ovarian stimulation and random start in assisted reproductive technologies: from ovarian biology to clinical application.
abstract: OBJECTIVE
  The opportunity to use gonadotropins to stimulate the growth of antral follicles coming from different follicular waves available in different moment of the menstrual cycle allowed the implementation of innovative protocols in assisted reproductive technologies. The purpose of this review is to explore the possible advantages related to these new controlled ovarian stimulation (COS) strategies.
  
  
  RESULTS
  Women exhibit major and minor wave patterns of ovarian follicular development during the menstrual cycle, as it is in animal species. These observations led to the introduction of two new strategies for COS: the random start and the double ovarian stimulation within a single menstrual cycle.
  
  
  CONCLUSIONS
  The use of gonadotropin-releasing hormone antagonist COS protocols, started randomly at any day of the menstrual cycle, is today a standard procedure in those cases where obtaining oocytes is an urgent task, such as in case of fertility preservation for malignant diseases or other medical indications.On the other hand, in poor prognosis patients, double ovarian stimulation has been suggested with the aim of maximizing the number of oocytes retrieved within a single menstrual cycle and, in turn increasing the chance to obtain a reproductively competent embryo. Randomized control trials are necessary to confirm these preliminary findings.
authors.affiliation: aGENERA Center for Reproductive Medicine, Valle Giulia Clinic, Rome bDepartment of Human Pathology, University of Messina, Messina cGENERA Center for Reproductive Medicine, Ruesch Clinic, Naples dDepartment of Obstetrics and Gynecology, 'Magna Graecia' University, Catanzaro eIRCCS, Policlinico San Donato, Università degli Studi di Milano, Milan, Italy fUniversity of Targu Mures, Targu Mures, Romania.
authors.forename: Alberto
authors.initials: A
authors.lastname: Vaiarelli
authors.forename: Roberta
authors.initials: R
authors.lastname: Venturella
authors.forename: Damiano
authors.initials: D
authors.lastname: Vizziello
authors.forename: Francesco
authors.initials: F
authors.lastname: Bulletti
authors.forename: Filippo M
authors.initials: FM
authors.lastname: Ubaldi
mesh_terms: D005260:Female; D005307:Fertilization in Vitro; D006801:Humans; D008597:Menstrual Cycle; D010062:Ovulation Induction / Q000379:methods*; D011966:Receptors, LHRH / Q000037:antagonists & inhibitors
chemical_list: D011966:Receptors, LHRH