Prolongation of the follicular phase in in vitro fertilization results in a lower ongoing pregnancy rate in cycles stimulated with recombinant follicle-stimulating hormone and gonadotropin-releasing hormone antagonists.
OBJECTIVE
To assess the effect of altering the timing of hCG administration on ongoing pregnancy rates in patients stimulated with recombinant FSH (rec-FSH) and GnRH antagonists for IVF.


METHODS
Prospective, randomized, controlled trial.


METHODS
Tertiary referral center.


METHODS
Four hundred thirteen patients undergoing IVF.


METHODS
Rec-FSH stimulation starting on day 2 of the cycle combined with daily GnRH antagonist starting on day 6 of stimulation. Patients were randomized to receive 10000 IU of hCG either as soon as at least three follicles were >or=17 mm on ultrasound (early-hCG group, 208 patients) or 2 days later after this criterion was met (late-hCG group, 205 patients).


METHODS
Ongoing pregnancy rate.


RESULTS
Fertilization rates and number and quality of embryos transferred did not differ between the two groups. However, a significantly lower ongoing pregnancy rate was present in the late-hCG as compared with the early-hCG group (25.0% vs. 35.6%, respectively).


CONCLUSIONS
Prolongation of the follicular phase in patients stimulated with rec-FSH and GnRH antagonists for IVF does not affect oocyte or embryo quality but is associated with a significantly lower ongoing pregnancy rate.
Kolibianakis
Efstratios M
EM
Centre for Reproductive Medicine, Dutch-Speaking Brussels Free University, Brussels, Belgium. stratis@easynet.be
Albano
Carola
C
Camus
Michel
M
Tournaye
Herman
H
Van Steirteghem
André C
AC
Devroey
Paul
P
D000328:Adult; D006063:Chorionic Gonadotropin / Q000008:administration & dosage*; D004334:Drug Administration Schedule; D005260:Female; D005307:Fertilization in Vitro; D005640:Follicle Stimulating Hormone / Q000627:therapeutic use*; D005498:Follicular Phase; D007987:Gonadotropin-Releasing Hormone / Q000037:antagonists & inhibitors*; D006728:Hormones / Q000627:therapeutic use*; D006801:Humans; D006080:Ovarian Follicle / Q000000981:diagnostic imaging; D010062:Ovulation Induction; D011247:Pregnancy; D018873:Pregnancy Rate; D011994:Recombinant Proteins / Q000627:therapeutic use; D013997:Time Factors; D014463:Ultrasonography
D006063:Chorionic Gonadotropin; D006728:Hormones; D011994:Recombinant Proteins; D007987:Gonadotropin-Releasing Hormone; D005640:Follicle Stimulating Hormone