title: Follicular phase endocrine characteristics during ovarian stimulation and GnRH antagonist cotreatment for IVF: RCT comparing recFSH initiated on cycle day 2 or 5.
abstract: BACKGROUND
  Strategies involving mild ovarian stimulation protocols for in vitro fertilization (IVF) might lessen discomfort to the patient and substantially lower complication rates.
  
  
  OBJECTIVE
  The objective of the study was to compare the follicular-phase endocrine characteristics and follicular development in patients who started recombinant FSH (recFSH) on cycle day (CD) 2 or CD5 in IVF treatment, using GnRH antagonist as comedication.
  
  
  METHODS
  This was a prospective randomized controlled trial in two university centers in Belgium and The Netherlands.
  
  
  METHODS
  Seventy-six IVF/intracytoplasmic sperm injection patients were included in the study.
  
  
  METHODS
  The control group (CD2) received a standard treatment with 150 IU recFSH from CD2, whereas in the study group (CD5), stimulation was started on d 5 of the cycle. The GnRH antagonist was administered daily from CD6 onward in both treatment arms.
  
  
  METHODS
  Endocrine follicular phase profile during ovarian stimulation was measured.
  
  
  RESULTS
  Follicular-phase patterns of gonadotropin and steroid concentrations were found to be comparable in both treatment groups, except for serum estradiol being significantly higher in the CD2 group on d 6 of the cycle (295.6 ± 202.5 ng/liter in the CD2 vs. 102.5 ± 47.9 ng/liter in the CD5 group; P < 0.01) and LH being significantly higher in the CD5 group on d 6 of the cycle (1.7 ± 0.7 IU/liter in the CD2 vs. 5.0 ± 2.1 IU/liter in the CD5 group; P < 0.01). With regard to follicular development, there was no difference in the numbers of small follicles (<10 mm), intermediate follicles (10-12 and > 12-14 mm) and large follicles (>14 mm) in both groups.
  
  
  CONCLUSIONS
  This study shows that the administration of recFSH starting on d 2 or d 5 of the cycle in a GnRH antagonist protocol for IVF/intracytoplasmic sperm injection patients yields a comparable endocrine profile and follicular development. Future studies should focus on the design of more patient-tailored ovarian stimulation protocols.
authors.affiliation: Centre for Reproductive Medicine, UZ Brussel, Laarbeeklaan 101, 1090 Brussels, Belgium. christophe.blockeel@uzbrussel.be
authors.forename: Christophe
authors.initials: C
authors.lastname: Blockeel
authors.forename: Monique D
authors.initials: MD
authors.lastname: Sterrenburg
authors.forename: Frank J
authors.initials: FJ
authors.lastname: Broekmans
authors.forename: Marinus J C
authors.initials: MJ
authors.lastname: Eijkemans
authors.forename: Johan
authors.initials: J
authors.lastname: Smitz
authors.forename: Paul
authors.initials: P
authors.lastname: Devroey
authors.forename: Bart C J M
authors.initials: BC
authors.lastname: Fauser
mesh_terms: D000328:Adult; D000465:Algorithms; D004334:Drug Administration Schedule; D004338:Drug Combinations; D005260:Female; D005300:Fertility Agents, Female / Q000008:administration & dosage*; D005307:Fertilization in Vitro / Q000379:methods*; D005640:Follicle Stimulating Hormone / Q000008:administration & dosage*; D005498:Follicular Phase / Q000097:blood*; D007987:Gonadotropin-Releasing Hormone / Q000037:antagonists & inhibitors; D006727:Hormone Antagonists / Q000008:administration & dosage; D006801:Humans; D008297:Male; D008597:Menstrual Cycle / Q000187:drug effects / Q000502:physiology; D010062:Ovulation Induction / Q000379:methods*; D011247:Pregnancy; D011994:Recombinant Proteins / Q000008:administration & dosage; D020554:Sperm Injections, Intracytoplasmic / Q000379:methods
chemical_list: D004338:Drug Combinations; D005300:Fertility Agents, Female; D006727:Hormone Antagonists; D011994:Recombinant Proteins; D007987:Gonadotropin-Releasing Hormone; D005640:Follicle Stimulating Hormone